Skip to main content

Full text of "Preliminary results from an operational 90-day manned test of a regenerative life support system"

See other formats


7/ 



N 



fKll 



NASA SP -261 



>of77 



FROM AN OPERATIONAL 90-DAY 

TIFF STTPPO"RT SVSTFM 



' . » .* * 



, i I ^ 1 . 1 1 



iE 



'4. 






* 'Sii. P* 



COPY 










% 



• "rt 



!•;,••.■ .' :.( ' ' /; i .. « ', = 



, I : ! 



;•' , -.t 



NASA SP-261 



PRELIMINARY RESULTS 

FROM AN OPERATIONAL 90-DAY 

MANNED TEST OF A REGENERATIVE 

LIFE SUPPORT SYSTEM 



A symposium held at 

Langley Research Center 

Hampton, Vitginia 

November 17-18, 1970 



Compiled by Albin O. Pearson and David C. Grana 
Prepared by Langley Research Center 




Scientific and Technical Information Office 1971 

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 

Washington, D.C. 



For sale by the National Technical information Service, Springfield, Virginia 22151 — Price $3.00 



FOBEWORD 



A 90-^ay manned test of a regenerative life support system in a space sta- 
tion simulator was completed on September 11, 19T0. This test was conducted by 
the McDonnell Douglas Astronautics Con^jany, Western Division, under contract 
MSl-8997 to 'the Langley Research Center, National Aeronautics and Space 
Administration, A number of unique investigations and studies were also con- 
ducted as an integral part of the test with, the principal investigators pro- 
vided by other HASA centers, Department of Defense, Department of Transportation, 
Atomic Energy Commission, industry, and •universities. Preliminary results 
obtained from this test were presented at a symposium held at the Langley 
Research Center, Hampton, Virginia, on November IJ and I8, 1970. Most of the 
investigators involved in the test, including those from McDonnell Douglas 
Astronautics Company and the Langley Research Center, presented their initial 
findings at this symposlTan, and these presentations are compiled in this doc- 
ument. It is emphasized that these resiilts are preliminary in nature, and it 
is ejcpected that more detailed, final reports will be issued at later dates. 



- iii - 



CON!BSHTS 



FOREWOED ,....., ..... ill 

1. mnomiE for mrnsRAnsD mm suppqet si^tems i 

Walton L. Jones 

2. TEST OBJECTIVES MD PROGRAM MANAGEMENT . 5 

J. K. Jackson 

3. FACILITy SUPPORT SYSTEMS .......... 17 

J. P. Valinslsy, R. L. Malin, and N. R. Radke 

k. LIFE! SUPPORT SISTEMS • • • • 55 

J. K. Jackson 

5. WATER MAUAGEMEm! k^ 

D. F. Putnam, E. C. Thomas, and G. V. Colom'bo 

6. DESIGN MD DEVELOPMEIMT OF THE YACUDM-DISTILLATIOK, VA^OR-FILTERED, 

ISOTOPIC-FUEEED WAEEIR RECOVERT SYSTEM FOR THE! 90-DAr MAITOEED 

SIMULATOR TEIST 91 

Courtney A, Metzger 

7. PEKF-ORMANCE EVALUATION OF THE THEIE?MAL CONDITIONING UNIT 99 

G. E. Allen 

8. PERFORMANCE OF THE COg CONCENTRATORS 107 

E. S. Mills and T. J. Linzey 

9. OPERATIONAL CHARACTERISTICS OF THE INTEGRATED SABAHER/TOXIN 

BURNER I3NIT 117 

J. F. Harkee 

10. PERFORMANCE OF A SOMD-AMENE CARBON DIOXIDE CONCENTRATOR DURING 

A 90-DAr MANNED TEST I5I 

Harlan F. Brose and Rex B. Martin 

11. ANALTSIS OP TRACE CONTAMINANTS ik^ 

P. P. Mader and J. K. Jackson 

12. MEASUREMENT OF TRACE ATMOSPHERIC CONSTITUENTS IN THE 90-DAI" 

SPACE STATION SIMULATOR * . . . 159 

M. L. Moberg and C. L. Deuel 

13. RESUIffS OF THE AEROSOL ANALYSIS EXPERIMENT PERFORMED DURING A 

90-DAY MANNED TEST OF AN ADVANCED REGENERATIVE LIFE 

SUPPORT SYSTEM 179 

Walter F. Harriott and Rotert A. Walter 



111-. WATER EIUCTROLYSIS STSIEJ^ I89 

E,. S. Mills 

15. aPEMTIOKAL CHAEACTEKESTICS OF A TWO-GAS CONTROLEER . 205 

J. F. Harkee 

16. LOCKHEED EffiCTROLySIS SISOIEM FOR THE KIMETy-nAI MAMED TEST 209 

Thomas M. Olcott and Barbara M. Greenough 

17. EVAIUATIOn OF A FOUR-GAS MASS SPECTROMETER USED FOR ATMOSPHERIC 

COHTROL DURING THE KINETr-DAT TEST 221 

Michael R. Rueker 

18. DESIGN AJSD OPERATION OF A WASTE, MANAGEMENT SISTEM FOR FECAL 

COLLECTION AND SAMPIOTG DURHTG THE 90- DAT MANNED SIMULATOR TEST . . ^^^ 
Courtney A. Metzger 

19. WASTE MANAGEMENT SUBSYSTEM . ^51 

J. K. Jackson and R. E. Shook 

20. FOOD MANAGEMENT PROGRAM 259 

J. S, Seeman and D. J. Mi/ers 

21. USE OF GETCEROL AS A DIET SOPPLEMENT DURING A NINETT-DAJ 

MANNED TEST 269 

Jacob Shapira 

22. MASS BALANCE DATA 277 

J. K. Jackson^ L. G. Barr, and J. F. Harkee 

23. THERMAL BALANCE DATA 295 

J. K. Jackson and G. E. Allen 

2k: ELECTRICAL POWER DISTRIBUTION AND USAGE 501 

J. K. Jackson and N. A. Jones 

25. MAINTENANCE AND REPAIR REQUIREMENTS 515 

M. S. Bonura 

26. DEVELOPMENT OF CREW SELECTION GUIDEHENES FOR THE 90-DAr MANNED 

TEST _ 525 

Rayford T. Saucer 

27. CREW SELECTION 529 

J. S. Seeman and M. V. McLean 

28. CREW TRAINING 559 

R. E. Shook and J. S. Seeman 

29. BEHAVIORAL PROGRAM 565 

J. S. Seeman and M. V. McLean 

vi 



50. MAMED MISSION ACTIVITY MAIiTSIS ....*.............. 577 

Earen Brender and Edward E. Regis 

51. HABITABILITY • 595 

J. S. Seeman, R. V. Singer, and M. V. McLean 

52. PSYCHCMOTOR PEKBX)RMA1TCE DURING THE 90-DflI MAINED TEST kl^ 

Rayford T. Saucer, Patrick A. Gainer, and Grady V. Maraman 

55. CREW PERFORMANCE ON SIMULATED CONTROL TASKS J+21 

R. Wade Allen and Henry R. Jex 

^. EEFECTS OF LONG DURATION CONFINEMEHJT ON SHORT-TERM MEMORT h^J 

R. Mark Patton and Clayton R. Coler 

55- NON-INTEKBHREDTCE PERFORMANCE ASSESSMENT (NIPA) . hkf 

M. M. Okanes, W. R. Feeney, and J. S. Seeman 

56. PSICHOLOGICAL ASSESSMENT OF CONilNED CREWS k6l 

Barry E. Collins, Joan Ranere, and Alvan Rosenthal 

57- BEHAVIORAL ACOUSTICS - THE IMPACT OF SPACE SIMULATOR NOISE ON 

CREW MEMBERS kjl 

Lawrence E. Langdon, Richard F. Gabriel, and Paiil A. Ahell 

58. EEG MONITORING/SLEEP STUDIES k79 

R. D. Joseph, W. B. Martin, and S. S. Viglione 

59. MEDICAL PROGRAM i^95 

J. R. Wamsley aoad D. J. Jfyers 

itO. MICROBIOLOGT RESUIffiS - DERMAL AND ENVIRONMENTAL SAMPLENG 517 

K. J. Levinson 

41. NASOPHARYNGEAL STUDIES 551 

Judd R. Wilkins 

k2. CHEMiniMINESCEHT BACTERIAL SENSOR 5^1 

Judd R. Wilkins 

k3. RADIATION SAFETY REPORT ON THE USE OF 25&Puq2 ^ ^ HEAT SOURCE .... 5^7 
A. A. Kelton 

kh. body: fiuid and body composition measurements 565 

A. A. Kelton 

k^. SOME BIOCHEMICAL DETERMINATIONS ON SERUM FROM CREWMEN 

PARTICIPAaiCNG IN A 9O-DAY SPACE STATION SIMULATOR TEST 575 

Edgar M. Neptune, Jr. , Richard E. Danziger, Terry L. Sallee, 
and David E. Uddin 



Vll 



k6. UTILIZATIOH OF TEE T-T SPIRQMETER LOOP OECHKIQUE FOR EESPIRATOEOr 

MOKITORIIG 585 

0. F. Trout, Jr., and T. 0. Wilson 

it-7. BLOOD CAEBOXYHEMOGLOBIN SATORATIOIf OF PERSOHKEL DUEIKG NINETT- 

MY TEST 591 

F. Lee Rodkey, Earold A. Collison, and John D. O'Neal 

1^8. SUMMAET MD CCMCmSIONS 599 

J. K. Jackson and Albin 0. Pearson 



viii 



RATIOHAIE FOR IMIEGEAIED. nCEE SUPPORT STSTEMS 

■Walton L. Jones, M. D. 
NASA Office of Advanced Research, and Technology 

The piirpose of this paper is to discuss the rationale for future inte- 
grated life support systems. Much professional effort has been expended in the 
past year on the 90-^y manned run and this effort has made a real contribution 
to the space program. All the participants have, at the same time, been eq.ually 
concerned with environmental problems. In the efforts to provide a closed 
ecology in a space cabin, the possibilities of applying these same concepts to 
earth's problems have been recognized. The resulting conservation of the eco- 
nomic and hximan resources will be most rewarding. It is an exciting matter to 
contemplate the development of technologies that may one day purify the waters 
of the earth and provide techniques for handling the ever more complex problems 
of waste disposal. It is believed that some of the most vexing problems now 
faced by the present society will be solved by the technologies which are the 
responsibility of the participants in this conference. In order to accomplish 
these goals within a reasonable time frame, there must be a carefixL coordination 
of "'■■"'^ us try and government efforts. 

jure 1 briefly summarizes the status of life support research and the 
p 3 expected to support missions in the 198O to 1985 time period. The ele- 
m hown are familiar to those closely involved in expediting these research 
p .s. 

le approach to reliable system development;, as is well known, must proceed 
2ful steps, from the conceptual stage, through subsystem development, 
-based tests, and finally integrated tests of total systems. The 60-day 
ndicated at the left of figure 1 demonstrated for the first time in an 
ed manned run that potable water could be recovered from urine and that 
maxji ^-luld consume this water without detriment to his health. In addition, the 
test demonstrated that unscheduled maintenance could provide a partial answer 
to the redundancy problem. 

The 90-<3-ay test is now complete and confidence in the ability to ultimately 
maintain man in a controlled ecology in the environment of space for chosen 
periods is being gained. However, it has indicated the need for automatic con- 
trol, modular configuration, and the usefulness of a larger crew for fut\ire 
longer ground tests. These tests will be most important, for cost will prohibit 
the building of complicated systems for extended tests in space flight. The 
answers must be determined economically here on the ground. These tests would 
proceed in logical increments. The first test might be the l80-day test that 
has been considered) later, a year- long test may be possible. 

The identification of the most competitive subsystems for such successive 
steps must be accomplished throxigh extensive ground tests that will yield valu- 
able performance data and experience. The 90- day test has, for example, singled 
out pacing technological problems. These problems must be solved before the 
l80-day ground test can begin. 



However, it must be remembered that in spite of all technical expertise, 
both in space and on earth, man is the most important component of the system. 
Iiife support systems which control his ecology must, therefore, obviously be 
designed to interrelate man's needs and capabilities closely. A number of 
elements above and beyond superior hardware design must be considered. The 
need to protect man's physical and psychological health will affect design con- 
siderably. For example, the full impact of exposure to prolonged weightless- 
ness on the human organism is not known. Mv,re definitive testing will be needed 
to tell whether some system of artificial gravity will be required. If this 
system does prove to be a need, the impact on the life support system design 
will be substantial. As other human- oriented constraints become identified, 
they will also have to be considered. Upper limits of toxic gases, the impor- 
tance of preserving in-flight samples of biological wastes for analysis, the 
psychological significance of volume constraints, food and water requirements, 
and the like, all affect regenerative system design. 

In addition to the problems of identifying the medically significant fac- 
tors for space missions, developing and designing effective subsystems, and 
selecting the most appropriate combinations for specific missions, there is a 
final requirement to study carefully the interrelation or interfaces of the 
equipment and the crew. The efficiency of the man-machine interface design 
represents an important variable in the determination of overall system effi- 
ciency. Eqiiipment built for use or operation by humans must be designed in 
terms of the best available information concerning human capabilities, prefer- 
ences, and frailties. Fortunately, a significant body of information of this 
class now is available in large part as a result of intensive research efforts 
conducted under the auspices of the National Aeronautics and Space 
Admini strati on. 




4) 



m 



TEST OBJECTIVES AND PROGRAM MANAGEMENT 

by J. K. Jackson 
McDonnell Douglas Astronautics Company 

SUMMARY 



Objectives of the 90-day operational manned test involved the evalua- 
tion o£ an advanced regenerative life support system similar to that of an 
orbiting scientific laboratory under closed-door conditions. These objectives 
included deterinination of long-term operating characteristics and power 
requirements of individual subsystems and the total system; measurenaent of 
mass and thermal balances; determination of the ability of the test crew to 
operate, maintain, and repair onboard equipment; measurement of chemical 
and microbial equilibrium of the closed ecological system; assessment of the 
effect of confinement on the psychological and physiological characteristics 
of the test crew; and collection of data to assist in determining the precise 
role of man in performing in-flight experiments. 

To implement the performance of this test a program mangement team 
was established by McDonnell Douglas Astronautics Company (MDAC). This 
group, headed by a Program Manager, included the necessary technical and 
scientific specialists to plan and execute the test program. The Program 
Manager reported to MDAC Senior Management and also served as the prin- 
cipal technical interface with the NASA program personnel. 

INTRODUCTION 

In the development of life support systems for advanced manned space- 
craft, extended manned tests of integrated systeras provide valuable data on 
the performance of subsystems under continuous operating conditions, the 
ability of the crew to operate and maintain them, and the requirements of the 
crew for maintenance of their physiological and psychological health for 
efficient accomplishment of mission objectives. 

The following papers present the results of such a test, for a period of 
90 days, using an advanced operational regenerative life support system 
under closed- door conditions. The test, performed in a Space Station Simu- 
lator (SSS), included the evaluation of a number of advanced life support sub- 
systems with backup provided by alternate subsystems that had undergone 
extensive manned testing. Data were obtained on the performance of the 
equipment, the men, and the man- system interface. The test was performed 
by MDAC under the direction of the NASA Langley Research Center and 
sponsored by the NASA Office of Advance Research and Technology. Results 
obtained by a number of other contractors and investigating agencies will also 
be presented. 




Previous tests of complete, manned life support systems have been 
performed by MDAC for a period of 60 days in the Space Station Simulator 
(refs. 1, 2, and 3) and by the NASA for 28 days in the Integrated Life Support 
System (ILSS) (ref. 4). The experience gained in performing these tests, 
and others of shorter duration, was applied in planning for the 90-day test. 
Features that were incorporated included advanced criteria for selection of 
the test crew, design of crew quarters, logistics planning, selection and 
design of subsystems, and data acquisition. These features were derived 
from the previous tests and assisted in improving the realism of the opera- 
tional simulation, as well as increasing the confidence in test completion and 
attainment of detail data for use in design of operational life support systems. 

TEST OBJECTIVES 



The 90- day test was planned to obtain complete data in the interacting 
effects of the crew and the life support system. To obtain these data, the 
foUow^ing objectives were established: 

A. To demonstrate a capability to operate a multi-man life support 
system in a continuous regenerative mode for a 90-day period without 
resupply. The system must provide a habitable atmosphere, food 
and water for nutritional support, and personal accommodations 
consistent with man's needs in the areas of personal hygiene, waste 
management, comfort and health. The system will include regenera- 
tive oxygen and water loops. It will be a goal to minimize the amount 
of stored expendable materials required for the test, 

B. To obtain total life support system and subsystem performance 
characteristics which include a material balance, a thermal balance, 
and power requirements. 

C. To operate with no materials passed into or out of the test chamber 
for the maximum possible duration to permit the chemical and micro- 
biological characteristics of the atraosphere, processes and hardware 
to reach operating equilibrium under man-loaded conditions and to 
determine the capability of the system and crew to operate without 
resupply. If resupply is required, it will continue to be an objective 
to hold the passing in and out of materials to a minimum and w^hen- 
ever feasible, materials to be passed into the chamber will be 
sterilized, 

D. To demonstrate man's capability to perform in-flight maintenance as 
a means of increasing system reliability and to demonstrate the 
capability for in-flight monitoring of the necessary human, environ- 
mental, and system parameters. 



E. To obtain through skillful planning, timelining, conducting, and 
analyzing pertinent onboard crew work activities, data which will 
assist in determining the precise role of man in performing in-flight 
experiments; assist in determining the practical benefits of manned 
activity in space; and assist in validating mathematical models of 
space missions. 

F. To obtain data on physiological and psychological effects of long- 
duration exposure of the crew to confinement in the cabin atmos- 
phere; on long-term group dynamics; and on crew^ -work rest cycles. 

G. To evaluate a number of advanced life support subsystems, using the 
proven subsystems of the SSS as backup, obtaining operating experi- 
ence and performance data under continuous testing and realistic 
conditions of manned loads and subsystem interaction. 

PROGRAM ORGANIZATION 

In order to manage the planning and operation of the test for MDAC, the 
program organization shown in figure 1 was established. Reporting to the 
program manager was a staff of specialists in technical and scientific areas 
to provide assistance in planning and execution of the test. His assistant 
was the Test Medical Director, responsible for the manned testing and 
medical aspects of the program. Business management support was also 
provided in areas of contracts, administration, and financial control. The 
program manager reported through the Chief Engineer of the Advance Bio- 
technology and Power Department to the MDAC senior management and served 
also as the principal point of contact with NASA for exchange of technical 
information. 

Figure 2 show^s the relationship of the 90-day test program organization 
to the MDAC senior organization structure. Although the direct line of com- 
mand was through the Advance Systems and Technology Subdivision, extensive 
support to the program w^as provided by the Development Engineering Sub- 
division. This support principally included the provision of facilities and 
technical services by the Engineering Liaboratories Department and constitu- 
tion and review of the Operational Readiness and Inspection Committee which 
reviewed the test planning and documentation from a standpoint of operational 
safety and presented findings to the Vice President/Development Engineering 
and to the NASA Langley Operational Readiness Review Comrhittee, 

TEST CREWMEN 

The four men who manned the SSS during the 90-day test performed many 
services which were essential to its successful completion. Among these 
services w^ere the collection of much of the data on mass balance, performance 



of highly skillful repairs on equipment, patient compliance with scheduled 
task assignments, collection and management of medical samples and physical 
data, and provision of much relevant psychological data by answering ques- 
tionnaires and operation of performance testing devices. Table 1 shows 
basic information on these men. The four backup crewmen who underwent 
the same training program and assisted in operations during the test also 
were a major factor in the program, 

CONTRIBUTING AGENCIES 



Many contributions*'to the success of the 90-day test we remade by 
scientists and engineers- from many Government agencies, universities, and 
industrial organizations, listed in Tables 2, 3, and 4, respectively. Repre- 
sentatives of many of these organizations will present resumies of their find- 
ings in following discussions. It is sincerely regretted that it is not possible 
for all to participate at this time. Much credit is due to those who are unable 
to participate in this discussion, as well as those are included. 

REFERENCES 

1. Jackson, J, K. , Bonura, M. S, , and Putnam, D. F.: Evaluation of a 

Closed Cycle Life Support System During a 60-Day Manned Test, 
SAE Paper 680741, SAE Journal, 1969, pp. 2832-2850. 

2. Bonura, M, S. , et. al, : 60 Day Manned Test of a Regenerative Life 

Support System with Oxygen and Water Recovery, Part I, Engineering 
Test Results. McDonnell Douglas Astronautics Company— West, NASA 
Report CR- 98500, December 1968. 

3. Taliaferro, E. H. , et. al. : 60- Day Manned Test of a Regenerative 

Life Support System with Oxygen and Water Recovery, Part II, 
Aerospace Medicine and Man-Machine Test Results. McDonnell 
Douglas Astronautics Company— West, NASA Report CR- 98501, 
December 1968. 

4. Pecoraro, J. W., Pearson, A. O. , Drake, G. L. , and Burnett, J. R. : 

Contribution of a Developmental Integrated Life Support System to 
Aerospace Technology. AIAA Paper No, 67-924 presented to AIAA 
Fourth Annual Meeting at Anaheim, California, October 23-27, 1967. 



UJ 
< Ui 

>E 



UJ 

-I 

UJ 



UJ 
OL 

X 

UJ 



QQ 
< 



UJ 
UJ 

o 

z 
o 



< 

o 



en 

O 
O 

X 



J2 

UJ 
UJ 

cc 
a 

UI 

o 



UJ - 

Q 



2 < 

<o 

p -J 

^ — 

09c _l 



UJ 

a. 

< UI 

cc I- 



-J »" r; 

occz 
2Q3: 
± m u 

~i < UJ 

u -J I- 






o 
cc 

o 

UI 



-,Z 

<z 

I- 1 
zu 

UI UJ 

s»- 

3CC 
CO 



UJ 
UJ ^ QC 



< 

Z eo 

QC ^ D 
iH UJ 



O 
t^ 

UJ 
H>- 

SujuJ 
*»■ -J 5 

UJ — < 
ocox 



> 

(3 
O 

^ O 
o Po 

U. t UJ 
t < Wu. 

SoSo 



UJ 

I- 
< 

UJ w 

*^ — m 
Q X > < 
UJ W ^ _J 
UJ < Z U 

tr S 3 D 



< 
o 

UJ Q 

auj 

ujS< 
-lOZ 

00c cc 
o <o 
Q>li: 

UJ0C_| 

UJ < < 

ccxu 



w 



> 
o 
o 

-J 

o 

z 
x 
o 

UJ 

H- 
u. 



lo 



o 
o 

UL ^ UJ 

"j I- I- 
< ^ t 



Z 

o 



O) 



(o cc 

0> < 
CQ I- S 






^ 



1 w 



Q. 



O) 



un v) 00 O 
(O cc (O oc 

O) rf 0> rf 

< >• w o X 
oarsiS 1-0. 



$ 



o 
cc 

UJ"< 



z 

UJ 



UJ 


M 


^_ 


(O 


CM 


a 


pg 


CO 


CM 


CM 


< 











z 

UI 
UI 

CC 

u 



o 

CO 
UJ 



< 
oc 
o 

> 

< CO 

X u 
UJ r; 

*" Ui 

oz 

ZUJ 
<C3 



OC 

I- 
co 



UJ 

X 

>-o 

QC _| 

SCO 

UJ> 

5£ 



CO 

u 

CO 

> 

X 
o. 

-I 

< 

u 
o 

UJ 



>> 

CC cc 

>■ CO CO 

ocujsi 

— O X I 

UJ O O O 
X UJ UI UI 
USOO 



oocb 

<^Z 

x±o 

UC7 cc 

S UJ < 



CO 

z 
z 

UJ 

o 

z 

UJ 

X 
&, 

UJ 



z 
o 
o 

> 
oc 

QC 
UJ 



oc 

UJ 

Q 



<8 

og 



z 

o 

z 

8 



Table 2 
PARTICIPATING GOVERNMENT AGENCIES 



NASA-Headquarters (PART) 
Direction 

NASA-LRC (Langley) 

Dirfection 

Two- Gas Control 

Four- Gas Spectrometer 

EEG 

Breath Analysis 

Crew Selection 

Psychomotor Tester 

Microbial Sensor 

Mission Analysis 

Zero-g Porous Plate H2O Separator 

Solid Amine CO2 Concentrator 

Pulmonary Function 

Zero-g Humidity Control 

Water Electrolysis 

Psychoacoustics 

Microbiologic Analyses 

NASA-ARC (Ames) 

Critical Task Tester 
Visual Tester 
Response Tester 
Glycerol Experiment 

NASA-MSC (Houston) 

Apollo Water Dispenser 

Urinal 

Tissue Dispenser 

Teflon-Coated Fiber glass 

Fluorel/Refset Elastomers 

Apollo- Type Crew Suits 

Fireproof Games 

Fireproof Paper 

PBI Fabrics 

Virus /Mycoplasma Analyses 

Vitamin D Assays 



USAF— Aerospace Medicine Laboratory 

VD-VF Water Recovery 
Commode 



AEC /Mound Lab 

Pu-238 Radioisotope Heaters 

U.S. Army/Natick Labs 
Freeze-Dried Foods 

NASA-MS FC (Hunts ville) 

CO2 Study 

Habitability Evaluation 
Skylab Light Level 

USN— Submarine Medical Research 
Laboratory (Groton) 

CO2 Blood Studies 

USN— Neuropsychiatric Research 
Institute (San Diego) 

Crew Selection 
EEG Studies 

U.S. Department of Transportation 
Particulate Sampling 

Naval Medical Research Institute 

Blood Analysis 
Crew Selection 
EEG Studies 



10 



Table 3 
PARTICIPATING UNIVERSITIES 



University of California at Los Angeles 

Noninterference Performance Analysis 
Test Crewmen 

University of Chicago 

Pico Library and Projectors 

Medical College of Virginia 
Potable Water Virology 

Texas Christian University 
Cre"w Selection Criteria 

California State College at Long Beach 
Psychodiagnostics 
Test Crewmen 

California Institute of Technolog y 
Test Crewmen 

University of Southern California 
Test Crewmen 



11 



Table 4 
CONTRIBUTING CONTRACTORS 



Aerojet- General 

Trace Contaminant Analysis 

General Electric 
Commode 

Litton (A the rt on Division) 
Microwave Oven 

Litton (Stouffer Foods) 
Frozen Prepared Foods 

MDAC-West 



Thermal Control 

Urine Collector 

Air Evaporator "Water Reclamation 

Molecular Sieve CO2 Concentrator 

Sabatier Reactor 

Two- Gas Control 

Life Support Monitor 

Wash Water Recovery 

Lockheed 

Zero-g Humidity 
Water Electrolysis 

Central Laboratories (Pico- Rivera) 
Clinical Analyses 

AiRe search 

Sabatier Reactor 
Li OH CO2 Removal 
Apollo H2O Dispenser 

3M Company 
Fluorel/Refset Elastomers 

Alii s - Chalme r s 
Water Electrolysis 

Aurora Engineering 
Autoclave Pass -Through 



Mine Safety Appliances 
Toxin Burner 

Scheufelin Papierfabrik Company 
Fireproof paper 

Per kin -Elmer 

Four-Gas Mass Spectrometer 

Dupont 

Teflon- Coated Fiber glass 

Monsanto 

Heat Transfer Fluid (Coolanol 35) 

Monsanto Chemstrand Division 
Durette Fabrics 

Monsanto Research/Mound 
Laboratories 

Radioisotope Heaters 

Massachusetts General Hospital 
Vitamin D Assays 

Hamilton- Standard 

Solid Amine CO2 Concentrator 

B. Welson 

Apollo- Type Crew Suits 

Parker Brothers 
Fireproof Games 

Celanese Corporation 

PBI Fabrics 

System Technology, Inc. 

Critical Task Tester 



12 



Table 4 (Continued) 



General Dynainics Corporation Fabric Research Corporation 

Response Analysis Tester Apollo- Type Crew Suits 

Oregon Fre eze Dry _,^ ... . , 
2 L Webb Associates 

Freeze Dried Foods 

Computer Communications, Inc. Metabolic Rate Meter 

Acoustic Data Link 

Warren E. Collins Douglas Aircraft Company 

Bicycle Ergometer Behavioral Acoustics 



15 



-^— ^ 


</) 


z 


a 


s 

UJ 


u 


£ 


^ 


< 


t 


>■ 


GO 


a» 


o 


i 


i 


5 


s 


u. 

UJ 


oc 
u 


C9 


X 


Ul 




o 





< 


1- 






Nl 


z 








s 

f7 






< 


oc 


tr 


oc 


o 


ULl 


Ui 
Ul 


UJ 
UJ 


o 


OC 
Ul 

o 


5 

z 

UJ 


a 

UJ 


S 


Q. 
Q 


Ik 

Ui 


Ik 

UJ 


< 


Z 
4 


X 

u 


X 


01 


> 


.- 


> 


o 


C9 

O 


S 


1- 

3 


o 


i_J 

o 




Ul 
Q 


(£ 


X 


■s. 




CL 




§ 


5 
u 


1- 


1- 
o 

s 


X 
X 


UJ 


Ui 

u 


^ 


1- 




< 
> 






> 


a 






< 








o 








1 

o 








O) 












GO 




< 


> 


-J 


■a 


t9 


c 








> 


UJ 


a.' 


UJ 

Z 






-» 


(9 








UJ 



S z 

"i 

. X 

-» o 

o 

K 

o. 



K 

O 



>> ec 
•a 



1- 

oc E 





o 


(A 


A 


H- 


E 


Z 


o 


UJ 


o 


S 


o 






K 


> 


Mf 




X 


o 


Ul 









u 


s 




3 




E 


K 


e 


Ul 


ca 


UJ 




Z 


o> 






U 


7 






Ul 



14 






> 

< 

o 
I 

o 

0> 



E 



I 

Id 

ea 



S 



LU 
UJ 



O 

H 



< 

o 
o 



u 




< 
a 

S 


oe 

UJ 

u 






QC 


u. 


UJ 


Lk 


u 


o 






u. 


(a 


o 






h- 


UJ 


< 


> 


cc 


1- 
o 


UJ 

o 


UJ 


1^ 


X 


UJ 


UJ 






z 


u. 


u 


UJ 




z 
u 


a 

z 
< 


a 

< 


UJ 


z 


Q 


< 


M 


S 


UJ 

K 


< 


^ 


z 




u 


ka 




3 




ea 






.a 




< 


u. 


cc 


S 


o 







H- 




Z 




UJ 


I- 
Sz 


a 


LOPM 
VISIO 


Ul 
E 

a. 

Ul 


UJ C9 


> 


a z 


■B 


WEST 
NEERI 


B 
O 


* z 


2 

a 


a S 


a: 


S 






X 




S 



CA 




Ul 








Z 

o 
15 


o 


E 


Ul 


O 


z 


m 




< 


a 


-J 


^ 




■o 


a 


o 


z 


4 


z 




UJ 


t- 


UJ 




Z 


u. 






a 








UJ 








» 





z 




UJ 




Ul 


cs 


z 


z 


ca 


l- 




M 


UJ 


UJ 


>- 




z 


X 


o 


o 


1- 


< 


< 


UJ 


z 


ea 


o 


z 


00 


o 


< 


1- 




u 


u. 


z 


Ul 






h- 


X 


z 


u 


3 


^ 


z 


>• 




o 








1- 




a.' 



> 




C9 


t- 


O 




-t 


Ul 


o 


o 


z 


c/> 


z 


UJ 


u 


z 


UJ 


a. 


1- 






UJ 


oS 


u 






CA 


> 


s 




Ul 


? 


>■ 


1 

B 


UJ 


£ 


u 

z 
< 


O 

a 


> 


—i 


a 




< 


ci 



s 



» 



$^ 



9 



> 




z 




o 

< 


u. 

UJ 


z 


z 


a 


tj 


ea 

< 
_j 


X 

u 

z 


z 


< 


o 


z 




ea 


1- 




< 


n 


3 


e 


S 


:f 






CO 






CJ 


Ul 




CJ 


GO 


< 




a. 




CO 





>■ 


z 


o 


o 


_j 


t- 


o 

z 


CJ 
UJ 

z 


u 


a 


UJ 




1- 


a 


00 


.e 




a. 


CO 




S 


E 


Ul 


'a 


t^ 


£• 


> 


SS 


CO 


!e 


UJ 
CJ 


■g 


< 


CO 

> 


> 


-» 


a 


■ 


< 


< 



s 



s 



» 



>■ 




z 




o 




1- 




<z 




zo 


■a 


ea < 


<z 

OZ 


"1 


zo 


& 


z o 


—3 


UJ 




z 








(S 








UJ 





K- 


z 


z 


o 


LU 

s 


s 


a. 


Ul 


O 


z 


mJ 




UJ 


a 


> 


^ 


UJ 

Q 


a 


a 


if 


z 




< 


B 






z 
u 
z 


'S 


< 


s 


UJ 




CO 


_J 


UJ 




z 





» 



» 



» 



CD 

•r-l 





z 




UJ 




ut 


z 


a> 


Ul 




s 


u 


o 


z 


£ 


UJ 


a 


u. 


UJ S 


UJ 

z 


z >■ 


CJ 


<C (9 


? 


> O 


a 


O -> 


S 


<o 




b' 


Z 


3 


o 


x; 


Ul 


5 

o 
Z 


O 


ea 


a 




X 




i£ 



A 



CO 




S 




UJ 




i^ 


u. 


>- 


Ul 


rr «" 


z 


UJ -t 


CJ 


a < 
< £ 

ip 


z 
u 

i 


S o 


ea 


< E 


e 


S > 


SI 


cs a: 


_ktf 


O Ul 


Si 


z ^ 




a. Q 




z 


^ 


< 




UJ 


-» 


u. 








.J 





« 



15 



FACILITY SUPPORT SYSTEMS 

By J. P. Valinsky, R. L. Malin, and N. R. Radke 

McDonnell Douglas Astronautics Company 

SUMMARY 



The facility for a 90-day manned test of a regenerative life support system 
is described including the support systems which were assembled to satisfy 
the program objectives and the safety requirements. Specific systems and 
equipment that are included are: the Space Station Simulator (SSS) chamber, 
the heating and cooling heat transfer loops, the electrical power system, the 
vacuum and freeze trap systems, the gas analysis system, the communica- 
tions system, and the data system. 

A review^ of the significant chronological events and resulting solutions 
will be discussed; also pertinent data, conclusions, and recommendations will 
be presented. 

The supporting laboratories w^hich included microbiological, water 
analysis, and medical, are described and their effectiveness is discussed. 

INTRODUCTION 



The facility systems for the 90-day manned test provided a test bed for 
the life support equipment and crew and the personnel protection provisions 
required to insure a safe test. 

The facility supplied electrical pow^er, heating and cooling fluids, gaseous 
nitrogen, and vacuum capability to the life support systems. Facility systems 
monitored the life support system performance and all the parameters critical 
to crew safety. Outside laboratories were used to provide medical analysis 
and to support the chemical and microbiological laboratories. 

The SSS (table 1) consists of a closed chamber and equipment necessary 
to evaluate a four-man crew and their life support systems under simulated 
Earth orbital space station conditions. 

The SSS chamber is a double-walled cylinder, 12 ft in diameter and 40 ft 
long. The 4,100-ft3 chamber contains a IBO-ft^ air lock and tw^o 18-in. - 
dianneter pass-through air locks, one equipped v/ith an autoclave for micro- 
biological control during pass -through operations. The chamber is operated 
at reduced atmospheric pressures to duplicate planned space cabin gas com- 
positions. The annular space between the inner and outer walls is evacuated 
to slightly belov7 cabin pressure, ensuring that all leakage is outboard to pro- 
vide realistic testing of environmental control and life support equipment. 
Chamber leakage averaged less than 1 lb/day during previous tests. The 

17 



chamber is provided with 4 in. of thermal insulation to nainimiize heat transfer 
and acoustic transmission. In the chamber, the noise-generating life support 
systems and experiments are separated from the crew living and recreation 
area by an acoustical barrier wall. 

COOLANOL SYSTEMS 



The cooling and heating requirenaents for the SSS life support and envi- 
ronmental control subsystems are fulfilled by two fluid conditioning and trans- 
port units. The cooling fluid facility (table 2) provides Coolanol 35 at 34° F to 
the thermal control unit, the carbon dioxide concentrators, the potable and 
wash water recovery unit, the Sabatier unit, and the electrolysis unit. The 
fluid heating facility (table 3) provides Coolanol 35 at 235 'F or 350°F to the 
carbon dioxide concentrators. 

The cooling fluid facility is located outside the SSS and consists of a 
90-gallon insulated storage tank; two Freon refrigeration systems to cool the 
Coolanol 35; a circulation pump for each system to force Coolanol 35 through 
the evaporator coils and back to the storage tank; and an external plumbing., 
system, with two pumps in parallel, to supply the Coolanol 36 to the SSS and 
return it to the storage tank. 

The heating fluid facility is also located outside the SSS and includes a 
45-gallon insulated storage tank, a 15-kW immersion heater within the tank 
to heat the Coolanol 35, a powerstat to control the voltage to the heater, a 
thermostat to control the temperature of the Coolanol 35 within the storage 
tank, and a circulation pump. 

ELECTRICAL POWER 

The electrical power required for operating the SSS subsystems and the 
support facilities includes the following (table 4): 

A. 400-cycle, 120/208-volt, three-phase. 

B. 60-cycle, 440-volt, three-phase (not available inside SSS). 

C. 60-cycle, 115-volt, single-phase. 

D. 28-volt dc. 

In addition, backup power is provided by a 400-cycle standby motor gen- 
erator set, a 28-Vdc power supply and an emergency 28-Vdc battery-operated 
system. The battery system is normally under a regulated trickle charge, 
but will auton^tatically supply power to critical circuits if the primary 28-Vdc 
supply is terminated. 

VACUUM FREEZE TRAP SYSTEM 

The vacuum freeze trap system consists of two parts (table 5). One 
portion, the waste manageinent vacuum system, serves the commode unit 

18 



of the waste management subsystem and the CO2 concentrator during bakeout 
cycles on the molecular sieves. The vacuum distillation-vapor filtration 
(VD-VF) vacuum system services the VD-VF potable water recovery unit. 
These systems are separated to prevent any possible bacterial contamination 
of the potable water system by the waste jnanagement system. 

The waste management vacuum system (fig. 1) consists of two mechanical 
roughing pumps, two cold traps, and a system for controlling the temperature 
and flow rate of gaseous nitrogen through coils in the cold traps. The VD-VF 
vacuum system is very similar in arrangement and operation to the waste 
management vacuum systena. It consists basically of two smiall cold traps, 
two vacuum pumps, and various valves and plumbing. The cold traps share 
the same temperature control systenn as the waste nnanagement vacuum 
systena. 

GAS ANALYSIS 



The composition of the SSS atmosphere during the manned operation was 
determined on a continuous basis and by individual samples taken at frequent 
intervals (table 6). Continuous analysis was performed by the gas analysis 
console (fig. 2). 

Representative samples of cabin air, taken frona one of 24 preselected 
locations (fig. 3), are compressed to sea-level pressure in the gas analysis 
console and can be withdrawn by syringe and needle technique for detail 
analysis by gas chrotnatograph or measured quantities can be passed through 
a liquid nitrogen freeze-out trap for concentration of organic trace 
contaminants. 

COMMUNICATIONS 

The SSS communications systein provides visual and auditory links 
between operating staff and crew members (table 7 and fig. 4) for: 

A. Monitoring the health and well-being of the crew at all times. 

B. Transnnission of audio-visual repair and nnaintenance information to 
the SSS crewmen. 

C. Provision of information for evaluation of man-machine interactions 
during manned tests. 

D. Transnnission of commercial TV and taped entertainnaent to crewmen. 

E. Recording of video and/or audio information from selected areas 
within the SSS. 

F. Recording of video and audio information during emergency 
situations. 

G. Control of all communications from one central console. 

19 



are: 



H. Outside telephone communication from normal intercom stations. 

I. Private channels of communication from selected intercom 
stations. 



INSTRUMENTATION AND DATA ACQUISITION 
The major systems used to acquire and display data, shown on figure 5, 

A. Low speed data system (LSDS). 

B. Life support monitor console (LSMC). 

C. Acoustical data link. 

Table 8 is a summary of data recorded on this system. 

The LSDS is a self-contained, general-purpose data acquisition and 
recording system. It accepts analog data from 10 mV to 5 volts, converts 
the data to digital values, and records on magnetic tape. 

The LSMC consists of a ■wide variety of signal conditioning and data dis- 
play instrunaents. This console provides on-line data displays and the audio 
and visual alarms of critical paranaeters. 

The acoustical data link provided a remote computer termiinal that was 
used to transmit and receive data to and from a remote computer using 
standard telephone lines. 

The terminal inside the SSS at the command console v/as used to summon 
crew subroutines and control the entry of raw data. It was also used to dis- 
play stored information as required by the crew. 

MICROBIOLOGICAL LABORATORY 



At specified intervals throughout the course of the test, microbiological 
analysis was performed on samiples of potable water, wash water, station 
surfaces, station atmosphere, and the nose and throat of the crew members. 
All equipnaent necessary for the collection and culture of the water samples 
was stored on board (table 9). 



CHEMICAL LABORATORY 



Chemical analysis of atmospheric trace contaminants, potable and wash 
water were performed in the laboratory located in same building as the SSS. 
Potable water samples were sent to the chemical laboratory at Santa Monica 
for metal analysis (table 10). 

20 



MEDICAL LABORATORY 

The medical laboratory was used to prepare samples for shipment to the 
supporting laboratories (table 11). 

SAFETY AND OPERATIONAL READINESS 



Safety and operational readiness reviews were conducted in preparation 
for manned testing in accordance with established MDAC procedures (Control 
Procedure CP 5. 61-C) and with NASA Langley Research Center Management 
Manual Instructions 1710. 1, 1710. 2, and 1710. 3. The sequence of events for 
these reviews is shown in figure 6. 

The MDAC Operational Readiness Inspection Committee (ORIC) was 
constituted by and reported to Mr. W. H. P. Drummond, Vice President of 
Development Engineering for MDAC-West. Membership of the ORIC was 
composed as shown in table 12. This committee provided a continuous and 
complete review of the safety aspects of the test during the planning stages, 
covering the subject matter shown on table 13. Tables 14 and 15 show some 
of the safety equipment included inside the SSS and nearby. Results of the 
ORIC review were presented to Mr. Drummond and to the NASA Operational 
Readiness Review Committee. 

The Operational Readiness Review Committee (ORR) was constituted by 
NASA LRC with Mr. H. A. Wilson as chairman. In addition to review of the 
test safety aspects, as presented by the ORIC, this committee also reviewed 
the test readiness from the standpoint of meeting contractual objectives. 



21 



VAC. PUMP 
NO. 1 



VAC. PUMP 
NO. 2 



DRAIN 



VENT 




COLD TRAP 
NO. 2 



ANNULUS 



l<pi MOLECULAR 
rV^ SIEVE UNIT 



_J^^^ WASTE MGM'T 



DRAIN ""'" W VENT 

Figure 1.- Waste management vacuum system plumbing schematic. 



d 



^'^^ 


=?°?^ 










2 




1 




(24 SAMPLE VALVES) ' 


' 












H2O 
ANALYZER 


L 












ffi^. 


r ^ 




1 




1 BACK PRESSURE 


^Vn ii 




OXYGEN 
ANALYZER 




^— * REGULATOR 


jp 1 > 






i 


(ONE ATMOSPHERE) 


CO2 
ANALYZER 








k 


I 








TOTAL 

HYDROCARBON 

ANALYZER 




HYDROGEN 
ANALYZER 




CARBON 

MONOXIDE 

ANALYZER 





Figure 2.- Gas analysis console system. 



22 







X 






f " -T— 








-J rS 








K 






in 


< 


tn 








n 

! 1 

1 




ro 


1 t 

1 1 
1 1 




1- 


1 






z 


1 




UJ ' 


I 






^ 1 






K 1 






^ 1 






1 i 1 






O 1 1 






t» 1 1 






*. 1 I 


« 




UJ 1 






K 1 


1 




u 1 


1 
• 


<0 


d 


> 1 
1 1 

r] 1 1 




T— 1 


|2l III 






L_J / |\- 






/ 1 V 






/ 


1 1 « 




■ 1 r 1 




1 1 

1 1 
1 1 


' «M 




1 <- 1 


««• n 




1 1 X* 1 




' '" ' 




sis / 




• 


15 k } 2"- 




S& N f 






etZ II 






UJO , \ 






1 1 


^^ 




1 1 








a 




I. J ~ 


(M 








L-. 1 



o 

1 

-a 


AIR EVAPORATOR BLOWER OUTLET 
AIR EVAPORATOR CHARCOAL BED INLET 
AIR EVAPORATOR CHARCOAL BED OUTLET 
AIR EVAPORATOR CONDENSER OUTLET 
TOXIN CONTROL OUTLET 
SABATIER CASE 
SOLID AMINE EXHAUST 
ELECTROLYSIS H2 TANK AREA 
ELECTROLYSIS CASE 
AIR LOCK 


CHANNEL 
NO. 


■ •••■■■■-•a 

«>4(<««tn«Di«>ao0)a<- 

«-«-«-«-«-v-<-i--CMC<J 


z 
o 

1 

o 


THERMAL CONTROL DUCT HX OUTLET 

EQUIPMENT AREA 

WASTE MANAGEMENT AREA 

FOOD PREPARATION AREA 

BUNK AREA 

FOOD STORAGE CABINET NO. 15 

FOOD STORAGE CABINET NO. 73 

COMMODE BLOWER OUTLET 

C02 CONDENSER SEPARATOR DISCHARGE 

C02 HEAT EXCHANGER INLET 

MOLECULAR SIEVE OUTLET 


CHANNEL 
NO. 





CQ 

•1-4 

o 

faD 

rt 

1—1 

i 

CO 

U 

s 

O 

& 
O 
•fH 

■^ 

o 
o 

J 

I 

CO 

CD 
U 

8, 



25 



C2 ® [d] 
^ IC-9 TV-11 



lC-10 
® C6 

(STORED) mm 
CI 



C5. 



IC-7 
® 



® 



IC-12 



TV-10 



IC-14 
^C3 



t 



IC-16 



lC-11 



lC-13 



C4 r- 



J] 



® lC-15 



LEGEND: 



SPACE STATION SIIVIUIATOR 



\9 IC-4 



AIR LOCK CONSOLE 



IB CAMERA , 
® INTERCOM 
[dJ TVAAONITOR 

Figure 4.- Space station simulator communications . 



SPACE STATION 
SMULATOR V 



LIFE SUPPORT 
MONITOR CONSOLE 



LOW SPEED DIGITAL SUBSYSTEM 



TGAS 



s 



tEMPERATURES 



PRESSURES 



FLOWS 



GAS SAMPLES 
AND/ OR 
SIGNALS 

=3 



TEMPERATURES 



TERMINAL 

COMMUNICATION 

LINK 

iTSCTh 



SIGNAL 
CONDITIONERS 



REFERENCE 
JUNCTIONS 



FREQTODC 
CONVERTER 



GAC 



DEW POINTER 



mV 



OHMS 



5V 



100 mV 



SPAN ID 



IV 



SAMPLE ID, 



INPUT RANGES: 
10 mV, 100 mV, IV & 5V 
FULL SCALE 
SAMPLE RATE 

1 SAMPLE/SEC/CHANNEL 



BRIDGE 
(BNC) 



FULL SCALE 
OUTPUT: 
1023 COUNTS 

FORMAT TO TAPE: 

FRAME SYNC, TIME-SEC,TIME-M1N 



TIME SHARE 
COMPUTER LINK 



TSCT- TIME SHARE COMPUTER 
TERMINAL 



Torm 

COMPUTER 

STORAGE AND/OR OUTPUT 

IN REPORT FORMAT 



TGAS- TWO GAS ATMOSPHERE 
SENSOR (PERKIN-EUVIER) 



Figure 5.- Life support instrumentation data management subsystem. 



2k 



TEST PLAN 

AND 

PROCEDURE 



SSS 

DESIGN 

REQUIREMENTS 




DESIGN 

REQUIREMENTS 

ESTABLISHED 


1 








GRIG 

REVIEW PER 
CP5.061-C 













SYSTEM 
DRAWINGS 



GRIG 
REVIEW 



SYSTEM 
ASSEMBLY 
AND G/0 



GRIG 
REVIEW 



GRIG 
APPROVAL 



ORR 

REVIEW 

PER 

LRC 1710.1 



ORR 
APPROVAL 




Figure 6.- Operational readiness review flow chart. 



25 



TABLE 1 
CHAMBER AND HABITABILITY FEATURES 



CHAMBER VOLUME 
CHAMBER PRESSURE 
CHAMBER TO ANNULUS AP 

AVERAGE TEMPERATURES 
CREW AREA 
BUNK AREA 
EQUIPMENT AREA 

AIR VELOCITY CREW AREA 
AVERAGE DEW POINT 
MEDIAN LIGHT LEVELS 

SKYUB 1ST MONTH 

CREW'S SEHING 3RD MONTH 



lOPSIA 



4100 CUBIC FEET, 116 CUBIC METERS 
517 TORR 
5 INCHES H2O, 9. 3 TORR 



74"F 


73°F 


78°F 


17FT/MIN 


58°F 


6 FOOT-CANDLES 


23 FOOT-CANDLES 



TABLE 2 
COLD COOLANOL 35 SYSTEM 

OPERATING PARAMETERS 



DELIVERY TEMPERATURE 


34°F 


DELIVERY PRESSURE 


lOOPSIG 


TOTAL FLOW RATE 


12 GALLONS /MINUTE 


AVERAGE HEAT LOAD 


44,000 BTU/HOUR 


SYSTEMS SERVICED 




THERMAL CONTROL 




POTABLE H2O RECOVERY AND HUMIDITY CONTROL 


SABATIER 




EI£CTR0LYS1S 




CO2 CONCENTRATOR 




VD-VF H2O RECOVERY 




SOLID AMINE 




ISOTOPE STORAGE 





26 



TABLE 3 
HOT COOLANOL 35 SYSTEM 



OPERATING PARAIVIETERS 
DELIVERY TEIV\PERATURE 
DELIVERY PRESSURE 
TOTAL FLOW RATE 
HEAT SUPPLIED 

SYSTEMS SERVICED 



235°F, 350°F 
50 PS I G 

5 GALLONS MINUTE 
14,000 BTU/HOUR 



00^ CONCENTRATOR - MOLECULAR SIEVE 
- SOLID AMINE 



SYSTEM FAILURES 

VALVE DIAPHRAGMS 
QUICK DISCONNECTS 
SUPPLY PUMP 



SEA LEVEL C/O 
UNMANNED BASELINE 
90-DAY TEST 



TABLE 4 
ELECTRICAL POWER 



TYPE 


AVERAGE LOAD 


120/208 VOLTS, 400 Hz, 3 PHASE 
110 VOLTS, 60 Hz, 1 PHASE 
28 VOLTS, DIRECT CURRENT 


2700 WATTS 
3450 WATTS 
1680 WATTS 



EMERGENCY POWER 

30 VOLT 200-AMPERE HOUR TRICKLE CHARGED BAHERY SYSTEM 
REDUNDANT BUILDING POWER SERVICE/AUTOMATIC SWITCHOVER 



POWER FAILURES 


DURATION 


4-26-70 UNMANNED BASELINE TEST 


5 SECONDS 


7-22-70 40TH DAY 90-DAY TEST 


3 SECONDS 


8-8-70 57TH DAY 90-DAY TEST 


8 SECONDS 



27 



TABLE 5 
VACUUM FREEZE TRAPS 



-70°TO-125°F 



WASTE MANAGEMENT AND MOLECUUR SIEVE 
FREEZE TRAP TEMPERATURE 
FREEZE TRAP PRESSURE 200MICRONS 

AVERAGE DA I LY H2O LOAD 0. 58 POUND 



VD-VF SYSTEM 

FREEZE TRAP TEMPERATURE 
FREEZE TRAP PRESSURE 



AVERAGE DAILY H^O LOAD 



-70° TO -125°F 



5T0RR 
0.47 POUND 



TABLE 6 




GAS ANALYSIS 


GAS ANALYSIS CONSOLE 




CO2 


INFRARED 


H2O 


INFRARED 


CO 


INFRARED 


TOTAL HYDROCARBONS 


FLAME IONIZATION 


OXYGEN 


PARAMAGNETIC 


HYDROGEN 


CATALYTIC OXIDIZER 


GAS CHRDMATOGRAPHS 




WET CHEMICAL ANALYSIS 





ATMOSPHERE CONTAMINANT SAMPLING SYSTETA 
FREEZE TRAPS 
CHARCOAL ADSORPTION 
DIRECT GAS SAMPLES 

OZONE DETECTOR 



28 



TABLE 7 
COMMUNICATIONS 



AUDIO 



16 STATION 3 CHANNEL INTERCOIVl WITH 2 CHANNEL RECORDING 

TELEPHONE 

mim RECEIVER 

CLOSED-CIRCUIT TV 

INSIDE SPACE STATION SIMULATOR 

5 FIXED CAIVIERAS WITH IV\ I CRO PHONES, 1 PORTABLE CAIVIERA 
2TVIVlONiTORS 

TEST CONTROL AREA 

1 PORTABLE CAMERA 

8 TV MONITORS. 1 STANDARD BROADCAST RECEIVER 

2 VI DEO TAPE RECORDERS 

VIDEO SPECIAL EFFECTS GENERATOR 

SYSTEM PROBLEMS 

IMAGING ON VIDICON TUBE 
AUDIO BACKGROUND NOISE 
HEAD SETS 



TABLE 8 
INSTRUMENTATION SUMMARY 

ENGINEERING PARAMETERS RECORDED 



TEMPERATURES 


120 


PRESSURES 


18 


FLOW 


23 


DEW POINT 


3 


ATMOSPHERE 


5 


EVENTS 


37 


WEIGHT 


10 


ELECTRICAL POWER 


7 


BIOMEDICAL PARAMETERS 





EKG 

ORAL TEMPERATURE 
METABOLIC RATE 
ERGOMETER WORKLOAD 
HEART RATE 



29 



TABLE 9 
WICROBiOLOaiCAL UBORATORY 

• REYNfERAlRSAMPieS 

• SURFACE SWABS 

• POTABIE H2O 

• WASH HgO 

• NOSE AND THROAT 
♦SKiH 

• POST 90-DAY TEST SAN\PLES - CREW AND HARDWARE 



TABLE 10 
CHEMICAt LABORATORY 

GAS ANAlYSiS WET CHEMISTRY 

OAILy-ALOEHyoeS, ANmOHih, 502. ^^Z 
TWICE PER WEEK - H2S, CL, HCL, PWSG£f€ 

WATER ANALYStS 

OWE SAMPIE PER TANK 

TURBIDITY AMMONIA 

COLOR TOTAL ORGANIC CARB<M4 

TASTE BRQWmE 

ODOR HEXAVALENT CHROWfUM 

ONE SAMPLE PER TWO WEEKS 

METAL ANALYSIS 8Y MOAC SANTA MOMICA CHEiyiJSTRY UBORATORY 



50 



BLOOD AND URINE 

BLOOD 

BLOOD 

THROAT CULTURES 
FECAL SAIVIPLES 
URINE SAAAPLES 



POTABLE WATER 
RESPIRATORY SAAAPLES 



TABLE 11 
MEDICAL LABORATORY 

COLLECTED AND PREPARED SAIV\PLES 



CLINICAL ANALYSIS 
STRESS AND CO 



CO2 EFFECTS 



BLOOD SERUIVl 



VIRUS 

ALVEOLAR GAS 
(EXPIRED AIR) 

VITAMIN D 



CENTRAL ANALYTICAL UB 

NIVIRI 

SUBMARINE MEDICAL CENTER 



VIRUS AND MYCOPLASMA - MSC 



MED COLL VA 
NASA LANGLEY 

MSC 



TABLE 12 

OPERATIONAL READINESS INSPECTION COMMITTEE 

ORIC 

• CHAIRMAN 

• EXECUTIVE SECRETARY 

• ELECTRICAL ENGINEERING 

• MECHANICAL ENGINEERING 

• SAFETY 

• QUALITY ASSURANCE 

• AEROSPACE MEDICINE 

• EMPLOYE RELATIONS 

• LEGAL 



31 



TABLE 13 

SPACE CABIN SIMULATOR 
FACTORS COVERED IN SAFETY REVIEW 

PERSONNEL TRAINING 

EMERGENCY EQUIPMENT AND PROCEDURES 

MATERIAL SELECTION AND CONTROL 

QUALITY ASSURANCE 

DOCUMENTATION AND CONFIGURATION CONTROL 

FAILURE EFFECTS ANALYSIS 

OPERATING PROCEDURES 

ELECTRICAL CIRCUIT DESIGN 

MEDICAL MONITORING 

FIRE DETECTION AND EXTINGUISHMENT 



32 



TABLF 14 
EMERGENCY EQUIPMENT - INSIDE SSS 



• AIR PACK BREATHING EQUIPMENT 

• POCKET RESPIRATORS 

• CO2 FIRE EXTINGUISHERS (4) 

• PORTABLE LIGHT 

• EAAERGENCY LIGHTING SYSTEIV\ (4) 

• BACKUP INTERCOM SYSTEM 

• WATER SPRAY SYSTEM 

• FIREHOSES (2) 



• SMOKE DETECTOR SYSTEM (6) 



• TRACE GAS MONITORING SYSTEM 



• EMERGENCY REPRESSURIZATION VALVE iCABIN) 



EMERGENCY REPRESSURIZATION VALVE (AIRLOCK) 



• AIR LOCK/CABIN EQUALIZATION VALVE 



WARNING SIREN AND BELL 



TABLE 15 
EMERGENCY EQUIPMENT OUTSIDE SSS 



BATTERY POWER SUPPLY (28VDC) 



• BATTERY POWER LIGHTS 



BACKUP INTERCOM 



REPRESSURIZATION VALVE ICABIN) 



REPRESSURIZATION VALVE (AIR LOCK) 



AIR LOCK/CABIN EQUALIZATION VALVE 



CABIN OVERPRESSURE RELIEF VALVE 



• SSS POWER SHUTOFF SWITCH 

• WARNING SIREN AND BELL 

• EMERGENCY ABORT SWITCH 

• FIRE/ SMOKE PROTECTIVE EQUIPMENT 

• CO2 EXTINGUISHER (100 LB) 

• MEDICAL TREATMENT FACILITIES 

• HOT-LINE TELEPHONE 



33 



LIFE SUPPORT SYSTEMS 
By J. K. Jackson 
McDonnell Douglas Astronautics Company 

SUMMARY 

The interior of the Space Station Simulator was redesigned to provide an 
equipment room, and a crew living area separated by an acoustic barrier. 
The life support equipment, operating instrumentation, and controls were 
located in the equipment room. Extensive provisions were made for acousti- 
cal control. The life support equipment included advanced units which were 
being operated for the first time in a manned test and baseline equipment 
which was available from the previously completed 60-day test. Integration 
of these units in such a manner that failure of a single unit did not jeopardize 
other test objectives was a major task of the systems engineers. The life 
support system included units for water management, thermal and humidity 
control, atmosphere purification, atmosphere supply and pressure control, 
waste management, and food management. 

INTRODUCTION 

The design requirements for the life support system used in the 90-day 
operational manned test included the following: 

Total Pressure 10 ± 0. 3 psia (517 ± 15 torr) 

Oxygen Partial Pressure 3. ± 0. 1 psia (155 ± 5 torr) 

Cabin Temperature 70 °F ± 5 °F (294°K ± 2. 8°K) 

Relative Humidity 40 to 70 percent 

CO2 Partial Pressure 0. 0735 psia (3. 8 torr) 

Diluent: Nitrogen 

All crew equipment, tools, and expendables were stored onboard at the 
start of the mission, eliminating the need for pass-in operations. Pass-out 
operations of medical samples required to verify the health of the crew and a 
linaited quantity of other material necessary for the collection of on- going 
test data were conducted once weekly through a small airlock equipped with 
an autoclave that was sterilized before each use. 



55 



SPACE STATION SIMULATOR DESIGN 

Figure 1 shows the configuration of the chamber that was used during the 
90- day test. This arrangement features an equipment room and crew living 
area separated by an acoustic barrier. The equipinent room includes all the 
mechanical equipment of the environmental control system and its operating 
instrumentation. A command center is located at the "front" of this room 
including the crew life support monitor, a psychomotor test console, and the 
computer- link keyboard. Computer input and output are displayed on a large 
video monitor visible through the forward viewport, but outside the chamber 
for ease of installation and maintenance. The crew living area includes 
space for food preparation, a folding table for eating and recreation, an 
onboard laboratory area, and an enclosed waste management area. Two 
bunks are located on each side of the air lock and are isolated from the main 
area by Armalon draperies. Much of the design of this installation was 
influenced by previous test experience which indicated equipment and living 
areas should be separated and that efficient noise control is very important. 

LIFE SUPPORT SYSTEM 

The design of the life support system involved consideration of the 
requirement for compact installation with ready accessibility for maintenance 
and repair. The evaluation of the advanced subsystems required extensive 
integration with the previously tested backup subsystems. This ensured 
continuation of the test when a naalfunction caused temporary or permanent 
shutdown of one or inore of the advanced subsystems, without compromising 
the remaining test objectives. Figure Z shows the interrelationships of most 
of the environmental control and life support units which will be described in 
more detail in the following discussion. These subsystems include: 

Water Management and Humidity Control 

Atmosphere Purification and Control 

Atmosphere Supply and Pressurization 

Waste Management 

Food Management 

Table 1 presents a list of the advanced subsystems and equipment that 
were evaluated, together with a list of backup and emergency units which 
were available for operation. In general, the advanced subsystems listed 
were not used previously in extended manned testing, or had undergone 
extensive revision since previous testing experience. They were used for 



56 



primary life support during the 90- day test. The backup subsystems had 
been extensively tested. Although they -were redesigned for the 90-day test, 
this was intended to improve maintainability or improve data collection, or 
to meet installation requirements. The interrelation between the advanced 
subsystems and backup units is generally indicated on figure 2. 

Detail descriptions of the life support subsystems and the results 
obtained from the 90- day test are presented in the following papers. 

A breakdown of weights and volumes of major items of life support 
equipment used in the 90-day test is included in table 2. Generally these 
units were not designed to meet flight weight, reliability, or structural 
requirements. However, these values may serve as a general guide, 
although they probably are usually much larger than would be found in a 
flight type design. 



57 









W 
Fh 
CO 

cq 
t3 
w 

Q 

u 

Q 

<; 

fn 

o 
o 

l-l 

<; 

< 
> 



a 



KM 


a 


0^ 


0) 
4-> 


t-{ 


W 





>« 


a 

w 


to 


p 


w 


2 


■ & 


<: 


J 


w 


o 


S 





4-1 

W 

o 

ni 
!> 

<! 



<0 
bO 

o 

-)-> 

CQ 

ni 
O 
.o 

o 



u 
o 

■u 
nj 

f^ 
O 

> 

W 
a 



o 
o 

r-l 
I 

P^ 
O 

u 
o 

> 
I 

o . 



3p^ 



«^ 



o 



TO •r^ 



;^ 

> 
o 
o 

M 
(U 

(!) 

1—1 

4J 
O 

0^ 



o 

•1-1 



> 

to 

nJ 

o 



■1} 

!-( 
^^ 

u ^ 

CO ""' 

<ri o 
^ jj 

.a a 

-^ O 
CO — 



•V 
.1-1 

o 
Q 

o 



o 
■j-> 

o 

Fi 
O 



(U 
O 

o 

t— I 

H 



O CQ 

;-i U 

<D a 

1—4 I— t 

.a • 

S to 



ou 



to 

o 

u 

o 

r-l 

W 



4-> 

>> 

1— I 

o 

S O 
•H O 

05 1-4 

o 



OC 



10 

05 

I 

O 

H 

T3 
^1 
ni 
O 

n r-H 

^ 2 

PQ o 



CQ 

Ou 

<! 



o 



;^ o 



p ii 



CO 

<u 

CL'-I 

w P 
o ^ 

a'S 

43 o 



to o 



o 



to 
O 



O 

u 

u 

Q) 
to 5 

o o 

r^ CO 

<! CO 



u 

.H 

4-" 

y 

I— I 
W 

i-H 

o! 

Cl 
0) 

r O 
^1 I 

CO <; 



0) 

o 

a 
a 

o 
O 



> 

o 

O o 





S 


a 


O 


too 


>H 




Oh 

^1 




Oh 


(U 




4.) 


■xf 


to 



O 


^ 


h 



38 



LU 



it 

o o 



o CO 



S 

5 



Cl. 

3 

UJ 

CM IJU 

all 



• « 

oo 'O- 



ir\ r-- CM CM "^ 
I— I CM •— * 



oo ^ NO 

r-» CM cr^ 



ITS 
CD NO C3 t-H f— (r% 



NO 



"^ Q S2 <t> 
NO lA o 



•?T CM CM 



S^^ 



oo 



cpi^o ooirjoooo 

C^i— l-^a- I^CMOO lR«5T 

NO U% CM I— « CM CM 



< 
s. 

< 
> 

UJ 



CO 



O 



CO S 



a: 

CO 



a 



o 

y 

—J 

o 
o 



a: 

< 



a: 5 o 

UJ *^ — I 

O < 31 

oo QC CO 



O 



O 
O 



Ng 

</> a: 

z > </> 
•< O ^ 
«— o 2 

5 Qi a: 
^ i±f |±f 

r! < < 



UJ 



CO 

o 



o 

a 

< 

X 

m 



>- 

CO 

en 

ID 



O a: 

O ID 



> 

o 

> 



13 O ^ *^ 



■-•-I ^^ 

^ Qs: 

— I— 
UJ CO Z 

Z Of O 

— ^ o 
< 3 < 
r; y Qi 



=3 




OO 


UJ 


•^ 


CO 


__ 


a: 


X 


UJ 


2 


5 


Ul 


< 
3: 




o 


h- 


1 


< 


K/\ 


CO 


_JI 


< 


_J 


CO < 



o 
o 

00 <2 
— <C 
CO o 

of 



oS2 



o 
a: 



O 
o 

CO 

O UJ 

O "J 

^^ 
P= O 

< UJ 

O Q- 
QQ CO 

Of ^ 



< 



CO 

< 



< 



< 



< 



Q. 
UJ 

«■&■■ 

CO 

o 



s 



o 



< 

>- 
—I 
Q- 

a. 

CO 
UJ 



co 

o 



59 



Ui 


> 


<D 


3 

u 


Z 


g 


< 


< 


QC 


1 


0^ 


«\ 


< K- 


oc 


uC III 


s 

z 


P f- 


o 


H ^ 


K 


< >: 


Z 


-J < 


1^ 


3 O 


2 


So 




</) o> 




z ^ 

is 




H 




< 




1- 




W 




UJ 




O 




< 




Q. 




(/) 









1^0 



oc 

< 
o 



> UJ 

o> 



HI 











2 




1- 






>- 




O 




z 














Ul 


a 

a 

u 

O 3 




WASH 

WATER 

RECOVEI 




FOOD 
STORAGE 
AND 
PREPARAT 




Ui 



>■ 

en 



0^ 

</> <o 

ijy 

UL o 

= O 
5 < 

O 



a 
z°<= 
— "-1- 

ooz 

H- OS 



Si if 



t 



Q DC 

= o 
X u 



<o 

S K 
lU Z — 

xoz 

I- U 3 



i 



— * 



£. X 
I- < 

< o 



i 



X 

o 

I- 
< 

X 




Lei 



< 

X 



^"^ M^ ^^ 

m GC « 

111 




I 



£2 < X 

3 H- Ci 



U3iVM 318Vi0d 



> 

X 

UJ 

u.o= > 

<. t CJ — 

a < UJ z 

>S X 3 



z •* 

S 1- 
< z 

m UJ 

E " 

_j esiZ 
O O O 
60 O u 



(A < 



*4- 



CO 



-X?<J- 



CM 
O 
U 



z 

X 



I- 

UJ 

X 



X 

o 

< 
eM<= 

o Z 

UJ 

UJ cj 

> 12 

UJ o 
C/0 CJ 



z 



. , UJ O 

Vx 1- 




CM 



•r-l 



X ec 
iiio 
I- I- 

BQ < 
(A X 



CM 

o 
o 



CO E 



o 
u 



X 

< 
o 

CO 

> 



!?<P 



UJ 2c 






M 



lto<-— I 







tn 












V) 


K 




> 


Ul 


1 1 


^ 


1- 


UJ 


o 


< 


-J 


K 


£ 


UJ 


H- 



CM 

o 



ra: 



In 



WATER MANAGEMENT 

By D. F. Putnam, E. C. Thomas, 
and G. V. Colombo 

McDonnell Douglas Astronautics Company 
SUMMARY 



Water management subsystemis used in the 90-day test were: (1) isotope- 
heated VD-VF unit; (2) wick evaporator and humidity control unit; (3) detoxi- 
fication-nnultifiltration unit; (4) potable water storage and distribution system; 
(5) backup potable water supply; and (6) wash water recovery unit. The per- 
formance data include mass and energy balances, water chemistry, and micro- 
biological profiles. Pretest qualification procedures are covered as well as 
operating procedures used during the manned test. 

INTRODUCTION 



This paper is one of a series that describes the results of a 4-man, 
90-day test conducted in the McDonnell Douglas Space Station Simulator with 
closed water and oxygen loops and no resupply. All expendables including 
food, pretreatment chemicals, filter beds, and machinery spare parts were 
stored onboard the SSS and no pass-ins were made during the test. 

SUBSYSTEM DESCRIPTIONS 



The water management subsystems are shown in figures 1 through 6. 
Figure 1 is a schematic which shows the interfacing between subsystems. 
Figure 2 is a photograph of the isotope -heated vacuum distillation- vapor 
filtration (VD-VF) unit and the wick evaporator and humidity control unit, as 
installed in the SSS. Figure 3 is a schematic of the wash water recovery unit, 
which was completely isolated from the potable water units. Figure 4 is a 
photograph of the wash water recovery unit showing the sink and the multi- 
filtration columns. Figure 5 is a photograph of the potable water storage and 
distribution system. The insulated, heated, storage tanks were hung from the 
overhead. Apart of the quick- disconnect water transfer and line-up station 
can be seen at the right of figure 2. Figure 6 is a scheraatic of the potable 
water storage and distribution system. It shows the MDAC cold water dis- 
penser and the parallel plumbed Apollo hot and cold water dispenser. 
Figure 6 also shows the backup potable water supply, which did not have to be 
used during the test. 

These subsystems are described in more detail below. 

^5 



VD-VF Unit 

The basic components of this unit were the urine accumulator, VD-VF 
boiler, water condenser, five radioisotope heat source capsules (plutonium 
-238 dioxide), and a radiation barrier water tank. The VD-VF unit recovered 
potable water from pretreated* urine and humidity condensate through the use 
of radio-isotope heat sources. Four of the five heat sources of 238Pu Oj,, 
each producing approximately 75 watts of thermal energy, were used in the 
boiler section to vaporize the urine mixture at about 100 °F and 0. 93 psia. 
The resulting vapor then passed through a porous matrix of Teflon and stain- 
less steel wire mesh and was superheated to 265 °F by the fifth isotope heat 
source of about 50-watt output. The vapor then passed through a catalyst bed, 
along with a snnall amount of bleed air supplied to oxidize the vaporized impuri- 
ties to carbon dioxide and water vapor; The water was then condensed and 
stored in an accumulator while the noncondensable gases were vented to an 
overboard vacuum cold trap. When the condensed water was chemically and 
microbiologically acceptable, it was p-umped directly to a storage tank. During 
periods of unacceptability because of taste, odor, or microbiological con- 
tamination, it was pumped to the detoxification-multifiltration unit for further 
processing. 

Radiation shielding was provided by a movable water jacket, which is 
shown in figure 5. A shielded, cooled storage facility was also provided 
inside the SSS for storage of the isotope capsules after removal from the 
VD-VF boiler. 



Wick Evaporator Unit 

The basic components of this unit are six wick packages, blower, carbon 
filter, particulate filter, and zero-g condenser separator. 

This unit was used as a backup for the VD-VF unit for recovering pot- 
able water from urine, processing excessive humidity condensate not used 
by the VD-VF unit, and for hunnidity control. When used to recover potable 
water from urine, the pretreated urine was pumped to one of the wick packages 
where heated cabin air from the blower evaporated the water, leaving the 
urine solids in the wick. The water vapor then passed through the carbon 
and particulate filters and through the condenser separator w;he re the water 
was removed and pumped to one of two zero-g holding tanks in the detoxi- 
fication-miultifiltration unit. The water was held at 160°F (344 °K) for a 
6-hour bacterial kill time and then multifiltered to one of the use tanks. 

When the unit was used for humidity control only, the air flow was by- 
passed around the wicks to the condenser separator. The separator in this 
unit, built by Lockheed Missile and Space Company, operates on a hydrophobic- 
hydrophilic principle. A fine mesh Teflon- coated stainless steel screen is 



*The nominal urine pretreatment was 4 ml /I of the following solution: 
39.8 percent H2SO4, 47.3 percent H2O, 9.8 percent CrOs, 3. 1 percent 
CUSO4, density = 1.42 g/ml. 



kk 



the liydrophobic element in the air stream, and an imcoated stainless steel 
screen is the hydrophilic element for removing the separated, water. 

The separated water could he removed in either of two ways: (l) a negative 
pressure cylinder, with a spring force equal to the hydrophilic screen differ- 
ential pressure rating, was filled from the separator a.nd then pumped to one 
of the two holding tanks or (2) the negative pressure cylinder could be filled by 
utilizing the differential pressure sensing switch and pumping system supplied 
as part of the condenser separator unit. 

Detoxification- Multifilt ration Unit 

The detoxification-multifiltration unit consisted of two zero-g holding 
tanks in which water was held for a minimum time of 6 hours at 160°F, a 
1- micron filter followed by an activated carbon colunan, two ion-exchange 
columns, and a final activated carbon column. Each column contained approxi- 
naately 0.2 lb of material. 

Potable Water Storage and Distribution System 

This system consisted of four heated zero-g storage tanks, distribution 
panel, circulation pump, 1-m.icron filter, chiller, MDAC dispensing unit, and 
Apollo hot and cold water dispensing unit. The system is shown schematically 
in figure 6. 

The four storage tanks are shown hanging from the overhead in their 
installed positions in figure 5. Figure 2 shows the flexible quick-disconnect 
lines on the distribution panel. The four storage tanks were used in 48-hour 
rotational sequence according to a plan in which the status at any time was 
one tank being filled, one tank being chemically and microbiologically checked, 
one tank certified potable awaiting use, and one tank being used. 

The distribution panel (fig. 2) contained movable piping connections and 
valving to place each of the potable tanks in its proper status. It also provided 
for a convenient location to draw samples at any time from any tank for micro- 
bial and chemical analyses. 

The circulation pump provided a continuous flow of hot water from the use 
tank to the use point and return, to prevent bacterial growth during nonusage 
in an otherwise stagnant line. 

Backup Potable Water Supply 

The backup potable water supply consisted of a stainless steel tank con- 
taining 400 lb of iodine-treated distilled water. This water was to be used in 
the event of complete failure of both the VD-VF unit and wick evaporator unit 
to produce potable water. The iodine level was maintained at 5 ppnn to provide 
microbiological control. 



Wash Water Recovery Unit 

This unit used multifiltration and heat sterilization to recover water for 
personal hygiene, laundry, and miscellaneous housecleaning chores. The 
basic components of this unit were two zero-g heated water tanks, multifiltra- 
tion module, heat exchanger, sink with mixing supply valve, pump, washer 
and dryer. Basic H, a concentrated organic, nondetergent, biodegradable 
cleansing agent was used in the unit. A schematic of the system is shown in 
figure 3. The multifiltration module consisted of a 30-, 3-, and 1 -micron 
filter series followed by an activated carbon column, two ion-exchange resin 
columns, and a final activated carbon column. 

In operation, the used water was pumped from the sink to the first heated 
tank and then processed automatically through the multifiltration nciodule to 
the second heated tank and is then ready to Tdc reused. The manually operated 
mixing supply valve proportioned the amount of water through the heat exchanger 
to provide the desired temperature. 



PRETEST QUALIFICATION 



Prior to the start of the 90-day test, the water managennent system was 
operated with real urine for 3 weeks to obtain mechanical, chemical, and 
microbiological certification. The chemical results are shown in table 9 and 
the microbiological results are shown in table 1. During the checkout proce- 
dure, high levels of cadmium were initially found in water from tanks 4 and 5. 
A thorough inspection disclosed that a cadmium- plated brass fitting had inad- 
vertently been installed in the discharge port of tank 4. It was also discovered 
that cadnnium was leaching from a similar fitting in one of the VD-VF boilers. 
After both fittings were replaced, no further high cadmium levels were 
detected. A small amount of microbial contannination was found in two of the 
storage tanks (see table 1), but in repeated tests at a later date, no contami- 
nation was found. Both taste tests and consumption tests were run, with the 
crewmen participating, and the reclaimed water was found acceptable. A 
silver-ion generator, which had been installed in the systenn for microbiologi- 
cal control, did not pass qualification tests because of insufficient ion concen- 
tration and high microbe levels downstream of the generator. 

The microbiological procedures used to qualify the system and produce 
the results shown in table 1 were in accordance with the National Academy of 
Sciences ad hoc Committee's recommendations for "water quality standards for 
long-diiration manned space missions (unpublished). 

This committee recommended that microbiological sampling during sys- 
tem qualification include testing for aerobic organisms (both gram negative 
and gram positive)^ anaerobic organisms, fungal organisms, and viruses. 

The procedure used for bacteria and fungi was that recomrnended in 
reference 1. All isolated organisms were subcultured to specific differential 
media for identification as shown in figures 7 and 8. 



Testing Procedure for Bacteria and Fiangi 

For the standard pour plate procedure, each santiple tested was collected, 

"by use of sterile techniques in Whirl-Pac hags and laheled with the collection 
site and date of collection. Duplicate po\ir plate serial dilution cultures 
were done on each specimen, incubating one at 57° C for kd hours for hacteria 
co\mts and one at 22° C (room temperature) for 7 days for fungi cotmts. 

A presumptive test for coliforms, by means of lactose broth fermentation 
tubes, was also done using 2 ml of the original water sample. 

One milliliter of each water sample was also inoculated into Thiogly- 
collate Mediumi, which pernaits the growth of the strictest anaerobic as well as 
aerobic organisms. 

Differentiation of Organisms 

If aerobic growth appeared in the Thioglycollate Medium, this culture was 
subcultured onto Blood Agar, Eosin Methylene Blue Agar, and Staphylococcus 
Medium No. 110 for identification. 

A. Blood Agar is a general nondifferential medium which will grow both gram 
negative and gram positive organisms. This medium was used as a 
backup source for any organisms isolated. 

B. losin Methylene Blue Agar is a differential plating medium which is selec- 
tive for grann negative organisms. Any organisms isolated on this mediunn 
were tested by means of biochemical reactions (such as citrate fermen- 
tation) for identification. 

C. Staphylococcus Medium No. 110 is selective for gram positive organisms, 
especially in the Staphylococcus group. Any growth on this medium was 
tested for the coagulase reaction which identifies Staphylococcus aureus. 

D. Fungus colonies which grew on the pour plate cultures incubated for 

7 days at room temperature were identified by their colonial morphology. 

Viruses 

Analyses for viruses were conducted at Virginia College of Medicine. 
During the 90 -day test all water was collected in sterile plastic bags fronn the 
Apollo hot water dispenser. Samples of approximately 250 ml were collected 
just prior to passout and stowed outside at -76° C ttntil shipment. 



hi 



OPIRATIHG PROCEDURE 



The protocol for maintaining the potable water system daily status and 
reclaimed water certification was as follows: water samples were delivered 
to the laboratory for analysis along with a chemical and physical analysis 
checkoff sheet (see fig. 9) and at the same time a Millipore Field Monitor was 
processed by the inside crew for bacterial analysis. The tank fill date and 
sample date were noted on a tank status card (see fig, 10) and as soon as avail- 
able the chemical and microbiological results were also noted on the card and 
the medical director then certified or rejected the tank for consumption. The 
system status and progression of tanks from fill status through certification 
to final use status was kept current on a system status board as shown in 
figure 11. 

The Millipore Field Monitors that were used for the enumeration and pre- 
liminary isolation of microorganisms were 0, 45 (jl, black, grid-type filters. 
Samples of water for microbial analysis were aseptically collected from each 
sampling port in a sterile disposable plastic bag after first flushing the sample 
port and then returning the initial 100 to 200 ml of water to the system via the 
urinal or sink. A fresh sterile field monitor and sampling tube assembly -was 
used for each water sample cultured. After identifying the field monitors as 
to sample port, date, time, and volume of sannple filtered (usually 10 ml), 
ampouled medium (Millipore v-^' M- TGE Broth) was added to each monitor and 
they were immediately incubated at 35° C for 48 hours. Following incubation 
the field monitors were opened and the membrane filters examined under 
illuminated low-power magnification for characteristic colonial growth. The 
total number of colonies present on each filter was counted and this count, 
divided by the volume of sample filtered, was recorded as the number of viable 
cells per milliliter of water. All field monitors shewing growth at ^8 hours 
were stored onboard at ambient temperature for weekly pas sout. In the out- 
side laboratory; representative colonies were selected and subcultured from 
each monitor for identification of genus and species. Field monitors showing 
no growth onboard were returned to the original storage container and held at 
ambient temperature for the duration of the test, 

PERFORMANCE 



Overall Water Balance 

A tabulated summary of the overall potable water balance is shown in 
table 2. It is significant that less than one-half of the reclaimed water was 
actually consumed by the crew. About one -fourth of the water was required 
to operate the solid amine unit and the remaining one -fourth was required to 
operate the VD-VF unit and for wash water makeup and samples. These data 
point up the need for realistic appraisals of the amount of reclaimed water 
that will ultimately be required in space vehicles in addition to the basic sur- 
vival requirements of the crewmen. 



1+8 



Detailed water balances for several significant periods of the test are 

presented In paper 22. 

VD-VF Unit 

Two VD-VF boiler units were used during the test for a total of 63 days of 
operation. The first boiler was used for 25 days and the second boiler was 
used for 38 days, of which only the last 27 days were continuous operation. A 
total of 1, 467 lb of urine and humidity condensate were fed to the units, which 
produced 1, 353 lb of water for a water recovery efficiency of 94. 3 percent. 
The net usable product was reduced to 1, 309 lb because of sampling require- 
naents an-d some substandard water that was rejected and reprocessed. Of 
this, 518 lb were used without multifiltration and 701 lb required multifiltration 
due to either poor taste or microbiological contamination. 

The mass and energy balance and the expendable requirements for VD-VF 
boiler 1 are shown in table 3. The requirements for VD-VF boiler 2 are 
shown in table 4. 

The major maintenance on this unit occurred after the switchover to the 
second holler. The first problem occurred during the initial fill of the new 
boiler when It was observed that the float switch did not shut off the urine feed 
solenoid valve. Draining and disassembly of the boiler revealed that the float 
retainer was off the shaft and the float was completely free. Repair was com- 
pleted and the boiler reassembled. During the next attempt to fill the boiler, 
the float switch wires were found shorted and a repair was made. The fill cycle 
was continued and the boiler overfilled and flooded the catalyst bed. This was 
thought to be the result of using the coarse Dwyer differential pressure switch 
circuit (normally used as a high boiler level warning light) to check out the 
float switch circuit, and then failing to return it to its proper status. The 
catalyst bed was removed, flushed with water, and then reassembled. A repeat 
of the flooded catalyst occurred and was found to be due to fused contacts on 
the float switch. Catalyst flushing and switch repair were performed again 
and the system restarted. A third flooding occurred after 11 days of opera- 
tion. The urine accumulator was inadvertently allowed to run dry and the 
cabin pressure forced the urine out of the boiler. Again, the catalyst was 
flushed, the system was restarted and remained operational for 27 days. Fig- 
ure 12 shows one of the boilers disassembled after the test. 

The remaining maintenance requirements consisted of using the onboard 
steam sterilizer six times to sterilize the condensate tanks whenever bacteria 
contanaination was observed. This procedure could not maintain condensate 
tank Sterility during most of the operation on the second boiler, in which case 
the product water was reprocessed in the detoxification-multifiltration unit. 

Wick Evaporator and Humidity Control Unit 

The wick evaporator operated a total of 31 days as a backup to the VD-VF 
unit. The humidity control portion of the unit operated for the entire 90 -day 

k9 



test. The wick evaporator was fed 700 lb of pretreated urine, flush water, and 
miscellaneous input, and produced 680 lb of water for a water recovery 
efficiency of 100 percent. Five wick packages were used. A mass and energy 
balance and the expendable requirements are shown in table 5. 

Premature flooding occurred in the first two wicks. The flooding was 
caused by a combination of (1) a higher feed rate than normal, and (2) unusually 
high humidity in the inlet air to the wick evaporator caused by the solid amine 
CO2 rennoval unit. The high feed rate, which was more than double that 
required to process the daily urine production, was used in an attempt to 
deplete the accumulation of urine created during VD-VF unit shutdown. Fig- 
ure 13 shows a typical disassembled wick package after the 90-day test. 

The 24-lb air carbon canister satisfactorily removed all urine odors 
during the entire 90 days, and was not considered expended at the end of the 
test. 

The zero-g condenser separator removed 5^ 172 Ih (35»2 lb/day) of 
humidity condensate and wick evaporator produced water. Of this water 
525 113 overflowed the separator and was processed from an overflow catch 
basin, and results in a water separation efficiency of 83.5 percent. This 
efficiency is excellent considering the separator was handling more than 200 
■percent of its design capacity. The hydrophilic screen sumps (three installed 
in unit) required frequent removal and cleaning to mininnize the amount of 
overflow. The frequency of cleaning varied, but averaged about every 3 days. 
Visual observation of the removed sumps did not reveal the cause of clogging. 

The alternate method of feeding the negative pressure cylinder was 
required after day 83 when the cylinder spring broke. The alternate method 
operated satisfactorily the remainder of the test. 

Detoxification- Multif iltration Unit 

The detoxification-multifiltration unit processed 1, 839 lb of reclaimed 
water and hunaidity condensate. The contributions to this total were: 414 lb 
from the VD-VF unit, 358 lb from the wick evaporator, and 1, 067 lb of 
humidity condensate. The carbon and resin colunans were changed three times 
during the test (see fig. 10). The reason for change was high NH3 level on two 
occasions and rapidly increasing TOO* on the third occasion, A total of 1. 2 lb 
of carbon and 1. 2 lb of resin were expended. A performance summary of this 
unit is shown in table 6. 

Potable Water Storage and Distribution System 

This systemi operated satisfactorily for the entire test with the exception 
of the cold water supply ports in the dispensing unit which becarae bacterially 
contaminated, and were not used after test day 3. The chemical (see fig. 14) 

and microbiological data are summarized in table ^ , which shows the certi- 
fied tank chemical and microbiological analyses. Table 8 summarizes all 



*Total organic carbon. 



50 



the microlDiological testing of the water management system done onlDoard 
during the test and table 9 shows the chemical analyses that were run 
biweekly during the test and also prior to the test during system qualifi- 
cation. The potable water dedly inventory is shown in figure 15. 

Backup Potable Water Supply 

The backup potable water supply was not required during the test. Weekly 
checks of the iodine content were naade to verify potability and the results of 
these analyses and a few microbiological checks are shown in table 10. Addi- 
tional iodine was not required to naaintain an acceptable minimum level. 

Wash Water Recovery Unit 

A summary water balance is shown in table 11 and results of the chemical, 
physical and naicrobiological analyses are shown on figure 16 and in table 12. 

The unit processed 11, 182 lb of water and used 24 lb of expendables. The 
multifiltration module required four changes of a carbon column, one change 
of both resin colunans, and replacement of five particulate filters at the time 
intervals shown on figure 16. Figure 17 shows the used filters. The neces- 
sary filter changes were dictated by their individual pressure drop increases 
and the column changes were dictated by crew judgment of water quality and 
chemical analysis results. The replacement of the filters and resin columns 
was a straightforward change, but the carbon column changes involved putting 
a new column in the last position and moving the old one into the first position. 

In addition to the 710 lb of phase changed water that were added as makeup 
to the system, there was one complete change of water on day 35 in which the 
used charge was replaced with 88 lb of hunaidity condensate. This was done 
after the first signs of crew rejection of the water. Five days later on day 40, 
the first carbon column was changed and a considerable imiprovement in water 
quality was noted. Microbial growth was found in the felt pad carbon retainer 
in the carbon column and it is felt that this growth was responsible for the 
objectionable odors. Both the carbon and resin columns were changed on day 
52 and probably would have been changed again on day 86 had it not been so 
close to the end of the test. 

The washer and dryer were used to clean and dry 44 loads of wash com- 
posed of underclothing, socks, unifornas, wash cloths, towels, and bed sheets. 

The power consumption of the wash water unit is shown in table 13. 



REFERENCE 

1. Standard Methods for the Examination of Water and Waste Water, 

American Public Health Association, 11th Edition, I960, New York. 

51 



Table 1 

POTABLE WATER SYSTEM PRETEST QUALIFICATION 
MICROBIOLOGICAL DATA 



Raw 
Date Urine 



MDAC 
Dispenser 



VD-VF 

Condensate 

{B-84) 



Tl T2 

(B-36) (B-38) 



T3 



T4 



T5 



T6' 



TB 



5-2-70 



5-20-70 







5-21-70 



5-22-70 



5-27-70 



6-2-70 



6-3-70 
















(1) 

299 





































































(2) 
16 







































































































6-9-70 



KEY: 



a b 



d c 

(1) 
(2) 



a = aerobes. No. /ml 
b = anaerobes, No. /ml 
c = fungi. No. /ml 
d = viruses. No. /ml 

Pseudomonas, Klebsiella Aerobacter 
Klebsiella Aerobacter, Staph. Epidermidis 



52 



Table 2 

POTABLE WATER SUBSYSTEMS SUMMARY 
WATER BALANCE 4 MEN, 90 DAYS 



Water Produced: 

Humidity control 

VD-VF 

Wick evaporator 
Water Used: 

ConsxHned by crew 

Feed to solid amine 

Feed to VD-VF 

Wash water makeup and phase change 

Samples, inventory gain, losses, etc. 



Pounds Pounds 





2,676 




1,353 




680 


2,045 




1,148 




644 




594 




278 





4,709 4,709 



Source of Water Constuned: 






VD-VF 




809 


Without post-filtration 


450 




With post -filtration 


359 
809 




Wick evaporator 




310 


Humidity condensate 




926 




2,045 



55 



TaHe 3 
VD-VF 1 BOILER MASS AND ENERGY BALANCE. 



Pretreated Urine = 289' 

Excess Pretreatment = 3 

Urinal Flush = 51 

Condensate = 209 

Reprocess - 29 

Miscellaneous = 11 

Total = 592 



25 Days of Qpe.ration 
17 Days witl^out Multifiltration 
8 Days with Multifiltration 



Air'= 0, 12' 



Water 
Air 



20.8 
0, 12 



VD-VF 
1 Boiler 



Water = 545 

(21.8 lb/day) 



Pretreated Urine Solids = 12. 
Excess Pretreatment = 1.5 
Water = 12.4 



Total = 25. 9 



Overall Water Recovery Efficiency ( 
Expendables: 



Water Out 
Water In 



Isotope Heat: 



Pretreatment Solution 

Boiler 

Catalyst 

MF Carbon 

MF Resin 

Antifoam 

Air Bleed 



■) = 94.3% 



2.2 

54.v4 

,4. 
0.11 
0. i 1 

,0.055 
0. 121 



Total := 60.996 



Boiler , =, 916. 8 Btu/hr (268.5 watts) 
Catalyst = 251.1 Btu/hr (73, 54 watts) 



Condenser Cooling (average) = 1, 238 Btu/hr (362 watts) 

Pumping Power (average) = 9 watts 
*A11 weights in pounds 



% 



Table 4 
VD-VF 2 BOILER MASS AND ENERGY BALANCE 



Pretreated Urine 
Urinal Flush 
Condensate 
Miscellaneous 



Total 



38 Days of Operation 

4 Days without Multifiltration 
34 Days with Multifiltration 



Water = 29.8 

Air = 0. 18 



394* 

70 
391 

20 

875 



Air = 0. 18 



VD-VF 
2 Boiler 



Water = 808 

(21.8 lb/day) 



Pretreated Urine Solids = 16.2 
Water = 20.6 

Total = 36. 8 



, Water Out. 



covers 
s: 




In:' = ^ 


•4. 


1/0 




Pretreatment Solution 


__ 


3.0 




Boiler 




= 


57.5 




Catalyst 




■= 


4.0 




MF Carbon 




= 


0.47 




MF Resin 




= 


0.47 




Antifoam 




= 


0. 084 




Air Bleed 




= 


0. 184 



Isotope Heat: 



Total = 65.708 



Boiler = 1004. 6 Btu/hf (294. 3 watts) 
Catalyst = 163. 2 Btu/hr ( 47.81 watts) 



Condenser cooling (average) = 1, 238 Btu/hr (362 watts) 



Pumping power (average) = 9 watts 



All weights in poimds 



55 



Table 5 

WICK EVAPORATOR MASS AND ENERGY BALANCE 
31 DAYS OF OPERATION 



Pretreated Urine = 483'' 

Urinal Flush = 86 

Condensate = 19 

Reprocess frorn VD-VF = 43 
Miscellaneous = 69 

Total - 700 



Wick 
Evaporator 



Water = 680 

(21.9 lb/day) 



Pretreated Urine Solids = 20. 
Water = 0. 

Total = 20. 



, Water Out, 



Expendables: 



uieu 


■^ ^ Water In 








Pre 


treatment Solution 


_ 


3. 


7 


Wic 


ks 


= 


17. 





MF 


Carbon 


= 


0. 


44 


MF Resin 


z: 


0. 


44 


Air 


„ , ^24 lb installed 
Carbon- ^ i i r 
not expended 

Total 


= 


-- 


-- 




21. 


58 



Heat (average) = 347 Btu/hr (101 watts) 



Condenser Cooling (average) = 360 Btu/hr (105 watts) 



Blower power =3 07 watts (includes humidity condensate) 



Pumping power (average) = 0. 7 watts 



*A11 weights in pounds 



56 



Table 6 

POTABLE WATER DETOXIFICATION MULTIFILTRATION 
UNIT 60 DAYS OF OPERATION 



VD- 


-VF 1 




79* 


VD- 


-VF 2 




335 


Wic 


k Evaporation = 




358 


Humidity Condensate = 


1 


,067 



Total = 1, 839 



Detoxification 

Multifiltration 
Unit 



Water 



1,839 

(30.7 lb/day) 



Water Out 
Overall Water Recovery Efficiency (-^vVaterTtr^ 

Expendables: 



Carbon 
Resin 



1.2 
1.2 



Total =2.4 



100% 



Hold Tank Heating (T^ and T^): 656 Btu/hr (163 watts) 



All weights in pounds 



57 



TABLE 7.- POTABLE WATER SYSTEM 



Date 


Tank 

No. 


Source 


PH , 


Specific 
Conductivity 

((imho-cm" ) 


TOC 
(mg/ e ) 


NHj 
(mg/ i ) 


Color 
(Cobalt 
units) 








No std 


No std 


No std 


l,pH>7 
10,pH<7 


15 


6-9t70 


3 


W. Evstp + 
dist H2O 


6.1 


2.5 


7 








6-9-70 


4 


VD-VF + 
dUt HgO 


6.4 r- ■ 


5.0 


5 





5 


6-16-70 


6 


VD-VF 


- 5. 1 %e 


38 


7.7 


1.4 


1 


6-18-70 


5 


VD-VF 


4.9 


18 


5 


0.6 





6-19-70 


5 


VD-VF 












6-20-70 


3 


VD-VF 


3.2 


15 


4 


0.5 


8 


6-22-70 


6 


VD-VF 


■ 5.2 


16 


5 


0.6 


2 


6-22-70 


4 


H, Cond. -MF 


6.7 


16 


11 


1,0 


1 


6-25-70 


5 


VD-VF 


5.4 


14 


3.5 


0.6 


2 


6-27-70 


3 


VD-VF + 
H. Cond. -MF 


5.2 


15 


7 


0.8 


5 


6-29-70 


6 


VD-VF + 
H. Cond. -MF 


5.5 


U 


9 


1.0 


4 


6-30-70 


4 


VD-VF 












7-1-70 


4 


Process T4 
through MF 


5.3 


16 


14 


1.1 


- 


7-4-70 


5 


VD-VF- MF 


5.7 


10 


17 


1.4 


3 


7-5-70 


3 


VD-VF-MF 


5.0 


14 


10 


3.0 





7-7-70 


6 


VD-VF-MF 


4.8 


17 


12 


2.9 


1 


7-11-70 


5 


W. Evap-MF 


5.5 


19 


14 


2.0 





7-14-70 


3 


W. Evap-MF 


4.7 


19 


15 


2.1 


- 


7-15-70 


6 


W. Evap-MF 


4.7 


21 


16 


1.3 





7-18-70 


4 


W. Evap + 
VD-VF-MF 


4.9 


18 


12 


0.5 





7-22-70 


5 


VD-VF + 
H. Cond. -MF 


4.8 


13 


8 


0.6 


1 


7-23-70 


6 


VD-VF.MF 


5.9 


37 


16 


3.0 


2 


7-26-70 


3 


VD-VF-MF 


6.6 


34 


9 


3.1 


1 


7-30-70 


4 


W, Evap-MF 


5.9 


4.5 


10 


1.0 


2 


8-1-70 


5 


W. Evap-MF 


5.7 


7,5 


12 


1.0 


2 


8-3-70 


6 


W. Evap-MF 


4.3 


42 


21 


1.2 





8-5-70 


3 


W. Evap-MF 


4.3 48 

anic Carbon 
Field. Monitor 
rou* to count 
sampling technique 
^ed 


27 


1.4 





Keys 


TOC 

MFM 
TNTC 
* 
MF 


Total Org 
= MUUpore 
= Too name 
= Incorrect 

MultUUte 





58 



CHEMICAL AND MICROBIOLOGICAL ANALYSES 



Odor 


Turbidity 

(Jackson 

units) 


Taste 


Foaining 


48- hr MFM 

VD-VF 

condensate 

(No. /ml) 


48-hr 

MFM 

tank 

(No. /ml) 


Date 
Certi- 
fied 


None 
objection- 
able 


10 


None 
objection- 
able 


None 

persistent 

>15 sec 


10 


10 




Very 
slight 


<5 


Slight 
medicinal 











6-11-70 


Bland 





Medicinal 





\ 





6-11-70 


Slight 





Slight 








• 


6-18-70 


Slight 





Very slight 








TNTC* ■ 
.0 


Retested 
6-21-70 


Slight 


<5 


Slight 











6-24-70 


Slight 


4 


Slight 











6-24-70 


Slight 





Flat 





- 





6-25-70 


Slight 


3 


Slight 











6-27-70 


Slight 
medicinal 


2 


Medicinal 





0. 1 





6-29-70 


Slight 
medicinal 


4 


Medicinal 











7-1-70 


Objection- 
able 




Objection- 
able 




0.4 . 





Rejected 


- 


2 


Strongly 
medicinal 


■ 








7-4-70 


Slight 
medicinal 


3 


Slight 
medicinal 











7-6-70 


Slight 


2 


Slight 
medicinal 











7-8-70 


Slight 





Slight 





0.4 





7-11-70 


Slight 


2 


Slight 





- 





7-13-70 


Slight 





Slight 





- 


. 


7-16-70 


Slight 





Flat 





- 





7-18-70 


Flat 


.0 


Flat 





9.6 





7-22-70 


Flat 


3 


Flat 





TNTC 


tf 


7-24-70' 


Flat 


3 


Flat 





■ 7.6 


0. 


7-27-70 


Flat 


3 


- 





300 





7-29-70 


Flat 


3 


Flat 





- 


• 


8-1-70 


Slight 


4 


Slight 





- 





8-4-70 


Flat 





Flat 





- 


,0 


8-5-70 


Flat 





Flat 





_ 





8-8-70 



59 



TABLE 7.- POTABLE WATER SYSTEM 



Date 


Tank 
No. 


Source 


pH 


Specific 
Conductivity 

(nmho-cnti" ) 


TOC 


NH^ 
(mg/ S. ) 


Color 

(Cobalt 

units) 






No std 


No std 


No 1 


std 


l,pH>7 
10,pH<7 


15 


8-7-70 


4 


W. Evap-MF 


4.4 


38 


25 




1.0 


2 


8-10-70 


5 


VD-VF-MF 


4.2 


44 


28 




1.8 





8-13-70 


6 


VD-VF 


7.0 


31 


9 




2,8 





8-16-70 


3 


VD-VF + 
H. Cond. -MF 


4.2 


42 


33 




1.0 





8-18-70 


4 


VD-VF + 
H, Cond. -MF 


6.7 


15 


10 




1.3 





8-20-70 


5 


VD-VF + 
H. Cond. -MF 


5.5 


15 


10 




1.2 


1 


8-24-70 


6 


VD-VF + 
H. Cond. -MF 


4.3 


38 


23 




1.4 


- 


8-27-70 


3 


VD-VF + 
H. Cond. -MF 


4.3 


32 


21 




2.2 


2 


8-30-70 


4 


VD-VF + 
H. Cond. -MF 


4.3 


29 


20 




1.7 





9-1-70 


5 


VD-VF + 
H. Cond. -MF 


4.6 


22 


18 




2.2 





9-4-70 


6 


W. Evap-MF 


6.7 


124 


26 




19.0 


1 


9-6-70 


3 


W. Evap-MF 


6.5 


15 


7 




2.5 


1 


9-9-70 


4 


W. Evap-MF 


5.4 


9 


13 




4,0 





Key: TOC 

MFM 

TNTC 

* 

MF 


= Total Organic Carbon 

Millipore Field Monitor 
= Too numerous to count 
= Incorrect sampling technique 
= Multifiltered 











60 



CHEMICAL AND MlCROBIOLOGICAiL ANALYSES (Concluded) 



Odor 


Turbidity 

(Jackson 

units) 


Taste 


Foaming 


48-hr MFM 

VD-VF 

condensate 

(No. /ml) 


48-hr 
MFM 
tank 
(No. /ml) 


Date 
Certi- 
fied 


None 
objection- 
able 


10 


None 
objection- 
able 


None 

persistent 

>15 sec 


10 


10 




Slight 


4 


- 





- 





8-10-70 


Slight 


2 


Slight 





2.6 





8-12-70 


Bland 


2 


Bland 





0. 3 





8-17-70 


Bland 





Bland 





37.0 





8-20-70 


Bland 


3 


Bland 





TNTC 





8-20-70 


Bland 


2 


Bland 





TNTC 





8-24-70 


Bland 


2 


Bland 





TNTC 





8-27-70 


Bland 


4 


Bland 





TNTC 





8-30-70 


None 


.2 


Bland 





TNTC 





9-2-70 


Bland 


2 


Bland 











9-5-70 


Bland 


3 


- 





- . 





Rejected 


Bland 


3 


Bland 





- 





9-9-70 


Bland 


2 


Bland 





- 





9-11-70 



6i 



H 

< 

D 

< 
u 

3 
o 
-J 
2 
n 
o 
« 
u 

«= 2 

« 
w 

H 
W 

m 
< 

o 

0- 









S ' 



0) "*i ^ — 



a o* 

iS 





u S 


■«■ 




< B 


u 




= 1 


h 


a 


■A 


} 










g 

o 


go~ 


o 



t-iQ 



o 

H 



o 

H 
Z 
H 



ts] ro xO 



u 


() 


H 


H 


2 


^, 


H 


H 



u 

H 
Z 
H 



U 
H 

Z 



O 

Z 
H 



o o o 



r- c^ [-- 



m vo r^ 00 



(*1 ^ ^0 f~- 03 (T- O 



>0 ^O >D ^O ^D ^O '^ 'C ^O >0 ^0 ^O ^O ^O ^0 *0 



sO r~- ta o^ o 






62 



<: 

H 

<; 
o 

►J 
< 
o 

o 
o 

o 

CO 3 

« o 
is u 



OS 

w 

H 

m 
<; 

o 









5 S.^! 



o 0° 

ex au9 
<; » —"" 





O 



hQ 



o 


U 




o 


O 


O 


O 


O 


O 


U 


o 


O 


O 


O 


(H 


H 


vO 


H 


H 


H 


H 


H 


H 


H 


H 


H 


H 


z 


2 


fvj 


rn 


Z 


Z 


2; 


2 


Z 


o Z 


Z 


Z 


Z 


Z 


H 


H 


■*' 


^ 


H 


H 


H 


tH 


H 


£ t^ 


H 


H 


H 


H 



se 



o o o o o o 
r^ i^ r- t^ r^ r- o 



o o o 



lii ■o r- cS o 



(M (M (VJ (M fvj 



r^ r- r- t^ t^ 

O ^^ ro m 



tn sO t^ 00 (T- o 



r- t^ [-- t^ 
tn ^ t^ 00 o^ o 



(M(V3(\]f>JfvJ(Mr'J(NJ(M(\J 



r^QOooaooocooooocoaoaooDooGOcooocococoQOoocoaococoQOoooocococo 



int^oooMco-^invD 



in in in 



00 a- o --^ 



■efin^or^ootr-o^^Mro 



*JD *-D ^D vD *^ vO ^O ^£i vO vO 



in vO r* no ty- O 

r- r- r^ r- r- 30 



65 



<! 

< 
Q 

< 
U 

o 
o 

o 

« g 

S a 

M 



Oi 

w 

H 
< 

W 

« 
< 

E-i 
O 

a. 




S 



o a) n 



O 0) Oo 









O^ O^ O^ O^ CT» O^ O^ CT^ O^ 






3S 



S " 

3 »H 



II ti 
o 

H 
Z 



64 



Table 9 
POTABLE WATER CHEMICAL PRETEST AND BIWEEKLY ANALYSIS 



Date 



Test 
Day 



Tank No. 



Source 



Analysis Results (mg/1) 



As 



Ba 



Cd 



cr 



Cr 



Cu 



Standard 



0.5 



2.0 



5.0 



0.05 



450 



N.S. 



5-25 
5-25 

5-25 
5-25 
5-25 
5-25 

5-31 
6-2 

6-3 

6-9 

6-9 

6-10 

6-16 

6-30 

7-13 

7-15 

7-21 

7-28 

a-11 

8-25 

9-7 



-18 
-18 

-18 
-18 
-18 
-18 

-12 
-10 

-9 
-3 
-3 
-2 
4 
18 
31 

35 

39 

46 

60 

74 

87 



1 
3 

4 
5 
6 
Backup 

Boiler 1 

Condensate 
Tank 1 

4 
Boiler 1 
Catalyst 
Cold trap 

6 

6 

5 



Condensate 
Tank 1 

6 



Distilled 

Distilled + wick evap 
M-F from Tank 2 

VD-VF, rejected* 

VD-VF, rejected* 

Distilled 

Iodine treated 
distilled 

VD-VF 

VD-VF 



VD-VF 

VD-VF 

VD-VF 

VD-VF 

VD-VF 

VD-VF 

Wick evap + humidity 
condensate M-F 

Wick evap + humidity 
condensate M-F 

VD-VF 

VD-VF + humidity 
condensate M-F 

VD-VF + humidity 
condensate M-F 

VD-VF + humidity 
condensate M-F 

Wick evap + humidity 
condensate M-F 



<0.001 
<0.001 

<0.001 
<0.001 
<0.001 
<0.001 



<1.0 
<1.0 

<1.0 
<L0 
<L0 
<1.0 



<1.0 
<1.0 

<1.0 
<1.0 
<1.0 
<L0 



<0.05 
<0.07 
<0.04 
<0.04 

<0.03 
<0.03 

<0.03 

<0.025 



<0.013 



<0.014 



<0.075 
<0.7 
<0.4 
<0.7 

<0.02 
<0.06 

<0.07 

<0.1 

<0.03 

0.019 

<0.093 



<0.075 
<7.0 
<4.0 
16.0 

<0.3 
<0.3 

<0.3 

<1.2 

<1.5 
0.08 
0.09 



<0.02 
<0.02 

0.49* 
0.05* 

<0.02 

<0.02 

<0.05 
<0.01 

<0.05 
0.008 

<0.005 
3.5 

<0.05 
0.009 
0.0015 

0.004 

0.003 

0.0006 

0.002 

0.002 



13.5 
15.2 

21.3 
9.6 

30.2 
6.0 



<0.04 
<0.04 

0.2 

0.2 

<0.04 

<0.04 



<0.001 
<0.001 

0.11 

0.005 

<0.001 

<0.001 



9.1 

22 

0.41 




<0.075 
0.08 
0.006 
1.0 

0.01 
0.006 

0.002 

0.005 



0.003 



0.001 



0.002 



<0.045 
0.03 
0.04 
0.6 

0.009 
0.015 

0.04 

0.002 

0.01 

0.013 

0.031 



0.06 



Incorrect sampling technique. 



65 



Table 9 
POTABLE WATER CHEMICAL PRETEST AND BIWEEKLY ANALYSIS (Continued) 



Date 


Test 
Day 


Tank No. 


Source 


Analysis Results (mg/1) 


Pb 


Se 


Ag 


SO4 


TDS 


NO3 

AsN 


NO2 

AsN 


Total 

N 


Standard 


0.2 


0.05 


0.5 


250 


1,000 


N.S. 


N.S. 


10 


5-25 


-18 


1 


Distilled 


<0.1 


<0.05 


0.0007 


<1.0 


146 


<0.1 


0.13 


<0.23 


5-25 


-18 


3 


Distilled + wick evap 
M-F from Tank 2 


<0.1 


<0.02 


0.0007 


4.5 


16 


<0.1 


0.13 


<0.23 


5-25 


-18 


4 


VD-VF, rejected* 


0.15 




0.001 


1.5 




6.4 


0.13 


6.53 


5-25 


-18 


5 


VD-VF, rejected* 


<0.1 


<0.05 


0.002 


2.0 




5.1 


0.10 


5.2 


5-25 


-18 


6 


Distilled 


<0.1 


<0.05 


0.003 


<L0 


16 


<0.1 


0.07 


<0.17 


5-25 


-18 


Backup 


Iodine treated 
distilled 


<0.1 


<0.05 


<0.0002 


26.0 


16 


8.65 


0.43 


9.08 


5-31 


-12 


Boiler 1 


VD-VF 


















6-2 


-10 


Condensate 
Tank 1 


VD-VF 


















6-3 


-9 


4 


VD-VF 


0.022 


<0.05 


<0.02 


<0.5 


156 


0.55 


0.38 


0.93 


6-9 


-3 


Boiler 1 


VD-VF 


<0.7 


<0.7 


0.03 












6-9 


-3 


Catalyst 


VD-VF 


<0.4 


<0.4 


0.001 












6-10 


-2 


Cold trap 


VD-VF 


0.46 


<0.7 


<0.03 






1.2 






6-16 


4 


6 


VD-VF 


















6-30 


18 


6 


VD-VF 


0.01 


<0.14 


0.004 







0.78 


0.06 


0.84 


7-13 


31 


5 


Wick evap + humidity 
condensate M-F 




<0.075 


0.004 




5 


1.0 


0.004 


1.004 


7-15 


35 


2 


Wick evap + humidity 
condensate M-F 


<0.003 


<0.08 


0.005 







<0.1 


0.05 


<0.15 


7-21 


39 


Condensate 
Tank 1 


VD-VF 


<0.002 


<0.25 


0.006 







<0.1 


0.035 


<0.135 


7-28 


46 


6 


VD-VF + humidity 
condensate M-F 


<0.006 


<0.3 


0.003 







<0.1 


0.1 


<0.2 


8-11 


60 


5 


VD-VF + humidity 
condensate M-F 


0.006 


<0.013 


0.011 










0.03 


0.03 


8-25 


74 


6 


VD-VF + humidity 
condensate M-F 


0.005 


0.013 


0.004 




10.0 





0.003 


0.003 


9-7 


87 


3 


Wick evap + humidity 
condensate M-F 










28.0 





0.008 


0.008 



Incorrect sampling technique. 



66 



Table 9 
POTABLE WATER CHEMICAL PRETEST AND BIWEEKLY ANALYSIS (Continued) 



Date 


Test 
Day 


Tank No. 


Source 


Analysis Results (mg/1) 


Al 


Be 


Bi 


Ca 


Co 


Fe 


Li 


Mg 


Standard 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


5-25 


-18 


1 


Distilled 




<0.002 


<1.0 


0.004 


<0.01 


<0.002 


<0.001 


0.02 


5-25 


-18 


3 


Distilled + wick evap 
M-F from Tank 2 




<0.002 


<L0 


0.05 


<0.01 


<0.002 


<0.001 


0.14 


5-25 


-18 


4 


VD-VF, rejected* 


0.53 


<0.002 


<1.0 


0.03 


<0.01 


1.75 


0.001 


0.04 


5-25 


-18 


5 


VD-VF, rejected* 


0.47 


<0.002 


<1.0 


0.02 


<0.01 


1.5 


<0.001 


0.02 


5-25 


-18 


6 


Distilled 




<0.002 


<1.0 


0.008 


<0.01 


<0.002 


<0.001 


0.02 


5-25 


-18 


Backup 


Iodine treated 
distilled 




<0.002 


<1.0 


0.008 


<0.01 


<0.002 


<0.001 


0.02 


5-31 


-12 


Boiler 1 


VD-VF 












0.1 






6-2 


-10 


Condensate 
Tank 1 


VD-VF 


















6-3 


-9 


4 


VD-VF 


0.038 


<0.0001 


<0.038 


0.18 


<0.002 


<0.38 


<0.0075 


0.045 


6-9 


-3 


Boiler 1 


VD-VF 


0.07 


.<0.03 


0.02 


0.1 


<0.03 


0.1 


<0.0007 


0.05 


6-9 


-3 


Catalyst 


VD-VF 


4.0 


<0.02 


<0.008 


0.3 


<0.02 


0.04 


0.001 


0.07 


6-10 


-2 


Cold trap 


VD-VF 


1.3 


<0.0007 


<0.006 


0.8 


0.03 


12 


0.001 


0.3 


6-16 


4 


6 


VD-VF 


















6-30 


18 


6 


VD-VF 


















7-13 


31 


5 


Wick evap + humidity 
condensate M-F 


1.7 


<0.0003 


0.002 


0.3 


<0.002 


0.08 


0.0002 


<0.06 


7-15 


35 


2 


Wick evap + humidity 
condensate M-F 


0.05 


<0.0003 


0.004 


0.04 


<0.002 


0.03 


<0.0002 


0.02 


7-21 


39 


Condensate 
Tank 1 


VD-VF 


0.01 


<0.005 


<0.003 


0.054 


<0.006 


0.014 


0.00008 


0.008 


7-28 


46 


6 


VD-VF + humidity 
condensate M-F 




<0.005 








0.044 






8-11 


60 


.5 


VD-VF + humidity 
condensate M-F 




0.0001 














8-25 


74 


6 


VD-VF + humidity 
condensate M-F 


















9-7 


87 


3 


Wick evap + humidity 
condensate M-F 



















Incorrect sampling technique. 



67 



Table 9 
POTABLE WATER CHEMICAL PRETEST AND BIWEEKLY ANALYSIS (Concluded) 



Date 


Test 
Day 


Tank No. 


Source 






Analysis Results 


(mg/1) 




Mn 


Hg 


Ni 


K 


Si 


Na 


Sn 


Zn 


Mo 


Standard 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


N.S. 


5-25 


-18 


1 


Distilled 


<0.01 


<0.1 


<0.05 


0.02 


0.3 


0.22 


<0.25 


<0.01 


<0.01 


5-25 


-18 


3 


Distilled + wick evap 
M-F from Tank 2 


<0.1 


<0.01 


<0.05 


0.64 


1.0 


0.38 


<0.25 


<0.014 


<0.01 


5-25 


-18 


4 


VD-VF, rejected* 


0.16 


<0.1 


0.9 


0.03 


0.8 


0.43 


<0.25 


0.27 


<0.01 


5-25 


-18 


5 


VD-VF, rejected* 


0.62 


<0.1 


0.9 


0.04 


<0.03 


0.19 


<0.25 


0.24 


<0.01 


5-25 


-18 


6 


Distilled 


<0.01 


<0.1 


<0.05 


0.01 


0.3 


0.3 


<0.25 


<0.01 


<0.01 


5-25 


-18 


Backup 


Iodine treated 
distilled 


0.08 


<0.1 


<0.05 


1.2 


<0.03 


0.3 


<0.25 


0.024 


<0.01 


5-31 


-12 


Boiler 1 


VD-VF 




















6-2 


-10 


Condensate 
Tank 1 


VD-VF 




















6-3 


-9 


4 


VD-VF 


<0.075 


<0.038 


0.38 


<0.038 


0.2 


<0.075 


0.02 


0.08 


0.003 


6-9 


-3 


Boiler 1 


VD-VF 


1.8 


<1.5 


1.3 


0.03 


0.2 


0.2 


0.07 


0.02 


<0.02 


6-9 


-3 


Catalyst 


VD-VF 


0.1 


<0.75 


0.01 


0.08 


0.1 


1.0 


0.08 


0.03 


<0.01 


6-10 


-2 


Cold trap 


VD-VF 


0.5 


<0.2 


2.2 


24 


0.5 


1.2 


<0.4 


0.8 


0.03 


6-16 


4 


6 


VD-VF 




















6-30 


18 


6 


VD-VF 




















7-13 


31 


5 


Wick evap + humidity 
condensate M-F 


0.004 


<0.075 


0.05 


0.21 




0.2 








7-15 


35 


2 


Wick evap + humidity 
condensate M-F 


0.13 


<0.08 


0.37 


0.04 


0.12 


0.05 


<0.02 


0.009 


0.008 


7-21 


39 


Condensate 
Tank 1 


VD-VF 


0.0044 


<0.04 


0.003 


0.025 


<0.04 


0.13 


<0.01 


0.012 


<0.004 


7-28 


46 


6 


VD-VF + humidity 
condensate M-F 




















8-11 


60 


5 


VD-VF + humidity 
condensate M-F 




















8-25 


74 


6 


VD-VF + humidity 
condensate M-F 




















9-7 


87 


3 


Wick evap + humidity 
condensate M-F 





















''Incorrect sampling technique. 



68 



Table 10 

DATA ON IODINE DISSIPATION IN BACKUP 

POTABLE WATER STORAGE TANK DURING 90 -DAY 

SPACE STATION SIMULATOR TEST 



Tank Design 

Type: 

Size: 

Material: 

Quantity: 
Water Chemistry 

Source: 



Cylinder with flat ends 

15-in. diameter X 66 in. - 14-gage shell, 12-gage ends 

Type 304 S/S-2B 

400 lb (50 gal) 



Sparkletts distilled drinking water. Specific conductivity 

= 3 to 5 |amho-cm ' 

Treatment: Add iodine solution 

(40 g I- + 52 g KI + 1, 000 g H-O) to reach 6 ppm/I as 
measured by the silver method. No additional solution added. 

I Dissipation Data 



Date 


Storage 
Day No. 


Ip Content 
(ppm) 


Millipore 

Field 
Monitor 
No. /ml 


Comment 


5-22-70 


1 


6 




Filled tank 


5-25 


4 


5 






6-2 


12 


5 







6-8 


18 


5 






6-13 


23 


-- 




Start 90 -day SSS test 


6-22 


32 


1* 






6-30 


40 


1* 






7-6 


46 


1* 






7-13 


53 


0. 5* 






7-13 


53 


0. 5* 







*Incorrect sampling procedure 



69 



Table 10 

DATA ON IODINE DISSIPATION IN BACKUP 

POTABLE WATER STORAGE TANK DURING 90 -DAY 

SPACE STATION SIMULATOR TEST (Concluded) 



I Dissipation Data (c 


ontinued) 




Date 


70 


Sto 


rage Day- 
No. 


h 


Content 
(ppm) 

4. 5 


Millipore 

Field 
Monitor 
No. /ml 


7-21- 




61 




7-21 






61 




5.0 




7-28 






68 




4. 5 




8-4 






75 




5,0 





8-11 






82 




5.0 





8-18 






89 




5.0 





8-25 






96 




5.0 




9-1 






103 




5.0 




9-8 






110 




5. 




9-10 






112 









9-24 






126 




5.0 





Comment 



End 90-day SSS test 
Emptied tank 



70 



Table 11 

WASH WATER SYSTEM SUMMARY 
WATER BALANCE AND EXPENDABLES 4 MEN, 90 DAYS 

Poimds Pounds 

Water Produced: 

Multifilfcration unit 11,182 

Water Used: 

,„ ,. flncluding evaporation") 10,448 

W^^^^^g (loss = 560 lb / 

Reprocess 500 

Urinal flush 207 

Phase change 88 

Miscellaneous 13 

Inventory change -74 



11,182 11,182 

Expendables: 

Four carbon columns 12 

Two resin columns 6 

Four particulate filters 2 

Cleansing agent (Basic H) 4 

Total expendables 24 

Heat: 

Tank heaters: 817 Btu/hr (239 watts) average 

Power: 

Pump: 1, 056 watts for 4. 32 hours total operating time 



71 



< 

s 

m 
o 

a! 
U 

3 
Q 

< 

<; 
y 

a. 

J 
<: 
o 

w 
u 

a! 
W 
H 

< 



8^ 



B 
O 

o 



" g 


o 




















•^ R 


o 




















S'^ 






















o • 






















Sl 


■a 












o 




O 


nO 


2 — 


o 




















2« 


U 






















F 






















o 




















.i? o 


vC 




















SK 






^ o 








o 




.-1 


C4 


Si 


Si 




















w 


5 


in 00 


— siJ 


^ <yv 


CO O^ 


CO CT^ 


^ Tf 


CM TJI 


sO vO 


^ o- 


Q 


CiO 


fo ra 


00 -* 


fO ^0 


o -^ 


r- t- 


r-* cr> 


vO 00 


00 (M 


O^vO 


H 


g 


— ^ 


N 


rp 


-" tN3 


ra in 


(M '^ 


■* 


r- 


^ vi) 



s 



s2 
f S 

3 a 



S ° 



nO o 


00 o 


>0 r-4 


00 o 


to I^ 


o m 



-- Ti* 


(M O 


OM 


•* ■* 


o -- 


o o 


(M to 


00 sO 


in o 


O^sO 


ts_ (^ 


CT^m 


in vO 


00 o 


—■ 


^ .-t 


^ 


^ ^ 


CO 


ro {\j 


(M 



(vj r- ^ 



-« 00 


to in 


O O 


in o 


ift in 


to h- 




r- o 


-. M 


CJ (M 


CO •* 


(M to 





o o 


o o 


CJ o^ 


in CO 


CO 00 




(>a CM 


,-4 ,-4 



o o 

CO 00 
CO CO 



o o 

(T-O 



CM O 

O Tf 



o in 

O 00 
to t\J 



in in 



o o 



■* r- 


in t^ 


00 o 


Tt< to 


>£| O 


h- 00 


•^ (M 


CM CO 


^ 00 


CM in 


o o 


cr-o 


sO sO 


CO CO 


to-* 


fO CO 


r- r- 


CO to 


r- r*- 


CO m 


to CO 


CO to 


CO CO 


m ^ 



^1 






a c 



22 




0) u 

s e 

O 

22 


4^^ 






4-> 

Ui CO 


aloi 





OJ si 


(U X! 


0} j:; 


(U ^ 


« X! 


(U ju 


C bo 


a M 


a bo 


a &£ 


a bo 


a bi 


Is 


o -^ 

2 CO 


2m 


2m 


O "ii 

2 m 


•'i 

2m 



m fo 






Tf U 



oU 



^o %o ^ ,-t 



^ ^ 00 00 



OO 00 



72 



Table 13 

POTABLE AND WASH WATER SYSTEMS 
POWER CONSUMPTION 



Kilowatt-hours 



Average Watts 
During Operation 



Potable Water System 

Holding Tank 1 

Holding Tank 2 

Use Tank 3 

Use Tank 4 

Use Tank 5 + Circulation pump 

Use Tank 6 

Humidity condensate pump, 
67-hour operation 

Wick Evaporator heater, 
1, 127-hour operation 



192 
158 
180 
161 
286 
206 
7 

374 



110-v Subtotal 


1, 


,564 


Humidity control blower, 400 Hz 




661 


Total 


2, 


,225 


Wash Water System. 






Use Tank 7 




244 


Process Tank 8 




271 


Sink pump, 4.32 -hour operation 




5 


Washer, 4-hour operation 




4 


Dryer, 44-hour operation 




82 


Total 




606 



89 
74 
83 
75 

133 
96 

104 

332 

986 

307 

1,293 

113 
126 
1,056 
1,000 
1,865 
4, 160 



73 







s 

0) 
+J 
. CQ 

>, 

Xi 
CO 

u 

CD 






ti^ 



Ik 



p©^i^1 



^*?4f.* 




Figure 2.- Potable water recovery unit. 



75 



£ 



o 
oc 

< 

o 



3= 



T 



£ 



o 

X 

Z 

o 



o 

< 

X 

o 



£ 



z 
o 

goc: 




Z 



T 



£ 



§ 






^i 








1^ 




4 

< Q 



1— HSM 



3 Sj g 
C > o 
_j =3 O 



>> 

> 
o 
o 



CO 



76 














V 
•A 










..*■■/■ 
J 






Figure 4.- Wash water subsystem filters and sink. 



77 




Figure 5.- Potable v/ater recovery units and water storage. 



78 




m 
>> 

CO 

o 
•1-1 

I 

•1-1 
u 

m 
•1-1 

u 

CD 
i—i 

i 

CO 

ai 
u 

§) 
■i-i 



79 




03 



•1-4 

s 

o 
o 

o 



be 

.1-4 

ri 
o 

la 

u 
o 

«4H 

u 

O 
O 
U 
PM 






•r-l 



80 



< 
< 



OQ 
LU 
LjJ 



O 













O 


CO 










UJ 








z 


UJ 












+ 


O 


+ 
O 

> 


z 

UJ 


o 

UJ 

a. 

CO 


> 


o 


+ 




O 








UJ 
O 


o 










toQi 




















LER' 
AGA 


O 


o 


CD 






o 




o 


UJ 

> 


^ 


< 


< 






< 


< 


^ 


o 


_ z 


^ 


l!^ 


2^ 






^ 


:k!: 


^ 




1 


1 






1 


1 


-J 


UJ O 
— 1 rv' 


< 


< 


< 






< 


< 


< 


LU 


•i^'± 


















UJ 






































to 








l/> 












O 








UJ 












^— 
o 




CO 


^UJ 










CO 


:f5 




^ 








s 




UJ 



iC- ^- =r 

o o o 



< 
o 



CO Cki 
> y< 

i= S£z 

LO "^i O 

O ^ ZZ 

Q 



CO 
O 

I— 

o 

< 



CO < cc 



< 

CO oo 



o 



— o 



o > 



o 
<: 



< < < 






< 



o o o 


CO 


< < r?i 


H 


UJ UJ LJJ 


CO 


CC QL^ 


■rH 




C 


UJ ui H 
> > m 


rt 


be 


1- ^ < 


o 


t/^ o °=^ 
O UJ <C 




> 


Q. Z > 


1^ 




bD 




(1) 




rt 


+ O > 


H 




d 




^H 




O 


Ge: 


« 

00 


o 




H- 


o 


< 


^1 


o 


f^n 


§s 


e 



^ z 



Qi: 



5 o 

z < 

-T ^ CQ 

:^ LU <-v 

o q: 2 

o ul °^ 

^^ "- UJ 

< < < 



o Ij 

t*J CO 

IC QQ 

O UJ 

UJ ^ 



O 

oc 

UJ 

:r 
o 

CO 



CO 

a: 
O 



o 
o 

UJ 



UJ 



< ^ 



z o 



Q^ UJ 
... O 



O 



± < 2 
—I IE 

< O Q 

^ O O 

< z < 

• • • • • • 

I o 

< z < 



UJ 



81 



TO: Dr. P. Mader 

FROM: Medical Director 90-Day Run 

SUBJECT: CHEMICAL AND PHYSICAL WATER ANALYSIS 

ACTION: Perform the analyses checked below 

Date of Sample 



Location of Sample 
Sample Number 



Source of Water: [ ] VD-VF 

( ] Humidity Condensate 
[ j Air Evaporation 



Actual Sample Size . 
Total plate count - 24 Hr . 
-48Hr. 

( ] Certified to use. 

Signed: 



mil 



.per mil 
.perm!!, 



Medical Ditectot 



Date 



Amount 



Standard 



Amount 



Standard 





[ ] Turbidity 
[ 1 Color 


(10) Jackson Units 
(15)Pt-CoUnits 


MEASURE 

EVERY 

TANK 


D [ ] Taste 
[ ] Odor 
[ ] Foaming 
[ 1 pH 
[ ] K 

Amount 


(none objectionable) 
(none objectionable) 
(none persistant >15 sec) 
(no std) 
(nostd) Atmho-cm'l 

Standard 



MEASURED 
EVERY 
2 WEEKS 



[ 1 As 

{ ] Ba 

[ ] B 

[ 1 Cd 

[ ] CI- 

[ ] Cr 

[ ] Cu 

[ J F 



MEASURED 
TO 

INITIALLY 
QUALIFY 
SYSTEM 
PRIOR TO 
START OF 
90-DAY TEST 



(0.5) mgll 
(2)mg/jl 
(5)mg/a 
(0.05) mg/2, 
(450) mgit 
(no std) mgll 
(3) mg/H 
(2) mg/£ 



Amount 



Standard 



Al 


(no std) mg/H 


Be 


(no std) mgli 


Bi 


(no std) mgll. 


Ca 


(no std) mgli 


Co 


(no std) mgll 


Fe 


(no std) mgll 


U 


(no std) mgll 


Mg 


(no std) mg/d 


Mn 


(no std) mgll 


Hg 


(no std) mgll 


Ni 


(no std) mgjl 


K 


(no std) mgJl 



I ] NH3 

[ ] TOC 

[ ] COD 

[ ] Br 

[ ] Cr+6 



l,pH >7 
10, pH <7 
(no std) mg/Jl 
(100) mgll 
(l)mg/il 
(0.05) mgll 



Pb 
Se 

Ag 

S0| 

TDS 

NO3 as N _ 

NO2 as N ~ 

Total N03~ 

andN02 

asN 



mg/n 



Amount 



Standard 

(0.2) mgll 
(0.05) mgll 
(0.5) mgll 
(250) mg/a 
(1,000) mg/il 
(no std) mgll 
(no std) mgll 



(10) mgll 



Amount 



Standard 



[ ] Si 


(no std) mgll 


[ ] Na 


(no std) mgll 


[ ] Sn 


(no std) mgll 


[ ■] Zn 


(no std) mg/)l 


[ ] P 


(no std) mgll 


[ ] Mo 


(no std) msll 



Figure 9.- Checkoff sheet. 



82 




o 



TANK N0._1 






i5_ s: 



START FILL f JLe. 
END FILL 0O 4^0 
SAMPLES TAKEN 
CERTIFIED: YES. ' ^ 
START USE - 
AMT IN TANK: _ 
AMT IN TANK: _ 
AMT IN TANK: _ 
AMT IN TANK: _ 
AMT IN TANK: _ 
END USE 

CERTIFIED: NO . 

REPROCESSED 

EMPTY, READY FOR REFILL 



MO 
7 



DAY 

aid 

3J- 



HOUR SIGNED 
Z2.IO &<4^ 



moo iTrw^gt^ 

ZZoo ^ 



^3 g. 

9^ _£ 



3 :^JTJ 




r 



o/oo -g^gr" 



^^ 



pH jL£5'C0L0R 
K 24L ODOR ^^£1. 
TOC _£_ TURBIDITY _£_ 
NH3 iti_ TASTE ZI_ 

• Ay* FOAMING ^^*^ 

TPC ^'^^ ' 



HEAT: YESjii. NO 

IODINE: YES N0£^ 



AgtQCN! YCO NO rr 



Figure 10,- Potable water tank status card. 



85 




a 

CD 
CO 

>> 

CO 
CD 

a 

cu 






<D 

•iH 






-»» 



■■ ! 

■'! ft 

■ iiiiiiiiiiiii ifiif 



8k 




■^ 



'MT^ ' ■'mmmmmm 



Figure 12.- VD/VF expended boiler. 



,f Vw^Sfc* I 



85 



-::^i 



A*' • 






5f ««i«r ■-».»■ 



*)w<iM|HMigiwy'i wijm &' ' 



— 3K*w% ' r!. ' «W'" 





.'Mifail ' • 



4^ 



Figure 13.- Expended wicks. 



86 




^ 




S8 




3 




CM 




r-i 






03 




•iH 


s 






i-H 




rt 




S 




rt 


NO 


^ 


u^ 


<U 




-M 


5 




«« <Q 


0) 


^H- 


1— 1 


to 


rt 


|ii 


^ 

a 


^ 


0) 




S 




•iH 




rt 


G^ 


p— 4 


er\ 


0) 




tf 




1 


^sr 


Tjl 


CM 


T-4 




0) 




^1 




?n 


>0 


•Jh 


1— « 


flH 



— oo 



^ m ir\ tr\ ifs o o 

fTV CM ■-• CM i-i 



^ r— if\ fr» 



(|_W0 SOHW^) 

AiiAiionaNOo oiJioads 



(uidd) 301 (Uidd) ^HN Hd 



siSAiVNV yaivM Jiaviod 



87 



oo 
oo 




^ 


8 


CD 


§ 


C3 
1— 1 


S 




^ 


9. 


s 


^ 


'd- 


"«* 


cr\ 


crs 


esi 


CM 


CM 


1—1 


1— 1 


1— 1 



o 

> 



•T3 

U 
O 

I— I 

ft 

I 



a» 

•r-( 



(81) 30N\nva - 39vyois miyni Jiaviod 



88 



{|.WDSOHWri) QNOOdS 




oo 
oo 



e\j 




r^ 






m 


^3- 


•>H 


NO 


>. 




1— ( 




rt 




§ 


NO 


W\* 


ITV 


»-i 




cu 




-•-> 




rt 




^ 


S5 


en 


o 


c§ 


1— 


^ 


to 


a 
••-1 






rt 




.— ( 


CM 


w 


crv 


cu 




K 


S 


• 
CD 

T-l 




a> 




;4 


NO 


5d 


1-4 


In 



oo 



CM 



(uidd) SQi 

SISAlVNVH3iVMHSVM 



O ^OO NO ^- CM 

(uidd) 301 



89 



30/j 



1st 
25 days 



Isl 
34 days 



2d 
27 diivs 




2d 
56 days 




Unu'jtd 



3d 
20 d::vs 



Last 
12 days 




3m 



' '-i 2d 

34 uays 56 days 



Figure 17.- Carbon column filters. 



.90 



DESIGN MD DEVELOPMfflT OF THE VACUUM- DISTILLA.TI01, 

VAPOR-ITLTERED, ISOTOPIC-FUEEED WAUR KECOVERT 

SISTEM FOR THE 9O-MY MAEHED SIMQIATOR TEST 

By Courtney A. Metzger 
Aerospace Medical Research Laboratory 
¥right-Patterson Air Force Base, Ohio 

SUMMARY 



The water recovery system for the 90-'3-ay manned- simulator test was fur- 
nished to the McDonnell Doiiglas Astronautics Company (MDAC) as an experimental 
system to recover potable water from pretreated urine and humidity condensate. 
This system, conceived and developed "by the Aerospace Medical Research Laboratory 
(AMRL), uses radioisotopes for thermal energy and is based on vacuum distilla- 
tion^ vapor filtration, and catalytic oxidation of the contaminants in the vapor. 
This paper describes the design and development of the system, called VD-VF. 
This is the first operation of a water recovery system which uses isotopes in a 
manned chamber and is considered a significant technological breakthrough. 

i 
HMRODUCTIOW 

Research conducted to obtain a process and a system design for the recovery 
of potable water from human waste during extensive space flights revealed that 
considerable thermal energy would be required for satisfactory operation. The 
large consumption of electrical energy prevents system acceptability when the 
energy drain is on the vehicle electrical supply system. The use of Isotopes 
as a source of energy was investigated and found to be acceptable. The vacuum- 
distillation, vapor- filtration (VD-VF), catalytic-oxidation water recovery 
system designed by the U.S. Air Force to be used with electrical energy was 
redesigned to accept radioisotopes. Specific isotopes were designed for inte- 
gration with the modified system. This report describes the design and devel- 
opment of the modified system. Results obtained by MDAC with the. system during 
the 90-day test are given in paper no, 5 of this symposium. 

SYSTEM DESCRIPTIOl 



Development 

The AMRL conducted an investigation (in I967-68) of methods to remove 
organic contaminants from waste vapors. One of the methods evaluated was 
vacuum distillation followed by catalytic pyrolysls of the vapor. Tests showed 



91 




that contaminant removal could be accomplished hy subjecting the catalyst to 
high temperature (1200° F). The J^MRL during this period of time also designed 
and developed a yacuum-distillation, vapor- filtered -water recovery system 
(VD-VP) described in references 1 to 5« While these developments were in prog- 
ress, the Arde Company of Mahwah^ New Jersey, developed a low-ten^erature cata- 

lyst, designated Ardox^^ , that showed promise. The YD-YF design permitted 
the incorporation of a unit containing the Ardox catalyst with a minimum modifi- 
cation of the system. To acconrplish this modification, the charcoal bed and 
top membrane were removed and replaced by a catalytic oxidation unit charged 
with the Ardox catalyst. The system was subjected to several JO-day tests in 
which electric heaters were used as the source of thermal energy. These tests 
showed that the low-temperat\ire catalytic-oxidation technique with vapor filtra- 
tion showed good potential for use in recovering high-quality sterile water 
from human waste. 

To qualify the VD-VF system further for space application, the AMEL initi- 
ated an in-house effort to design, develop, fabricate, test and evaluate a 
system with isotopes as the source of theimal energy, and the Atomic Energy 
Commission agreed to provide the required isotopes. The system was designed to 
operate continuously for a minimvim of 90 days, reclaiming potable water from 
2k pounds of human waste per day (9 pounds of urine and I5 pounds of atmospheric 
condensate). Figure 1 shows the general flow diagram for the system. 

The initial design consideration was to develop a system requiring a mini- 
mum of moving parts and maintenance. The use of isotopes eliminated electric 
heaters, which had exhibited a high percentage of failure. The final design 
resulted in only two pimips and a metering device for transporting the waste 
product from the storage tank to the evaporator and to remove recovered water 
from the water storage tank. The use of space vacuum and the vehicle coolant 
system for the condenser cqm$ileted the support required for operation. Approx- 
imately k pounds of the Ardox catalyst was used for each test. 

The system was subjected to two separate continuous runs of 39 days and 
36 days prior to the 90-day test. All urine processed was collected in a 
closed 6- liter container placed in a public rest room with no selection of the 
donors or control over their diet. Before the container was placed at the 
collection station, 15 ml of a kilik- mixture of sulfuric acid, chromium trioxide, 
and distilled water was placed in the urine collector along with 2 to 5 drops 
of antifoaming compound per liter. This pretreatment was necessary to prevent 
the breakdown of urea to ammonia. When 6 liters was collected, the container 
was taken to the laboratory and the measured urine was mixed with an equal 
vol\mie of distilled water to approximate a 50:50 mixture of urine and atmospheric 
condensate. This solution was then poured in the urine storage tank. A timer 
in the system allowed approximately J+OO ml of the solution to be pumped from 
the storage tank into the evaporator every 20 minutes. 

Evaporation occurs at temperatures between 100° to 120° F at pressxares of 

kO to 75 Bim Hg. The vapor passes through a 0.4- micron Pall Ultipor™ filter 
to remove microbial contaminants (a backup filter can be incorporated as shown 
in fig. 1) and then through the catalyst. The catalytic-oxidation unit is 

92 



maintained at 2^4-0° to 280° F. If any organisms pass through the filter, they 
are apparently removed hy the catalyst. The -vapor leaves the catalytic- 
oxidation unit through a tube which passes through the evaporator, where most 
of the heat is given up. The vapors are then passed through the condenser and 
the water is condensed and stored for future use. Once the waste solution 
enters the pump, and until the potable water is pianped off, the process is 
under vacuum. A flowmeter installed at the beginning of the process meters 
approximately 12 to 1^ cm? of room air per minute needed for the catalytic oxi- 
dation of the vapors. 

The Isotopes maintain the temperature in the evaporator at 100° to 120° F. 
The ten^jeratixre in the evaporator is the key to satisfactory operation of the 
system. The volume of waste and the pressure in the evaporator control the 
temperature when the isotopes are used to supply the theimal energy. System 
failiire can be caused by any one of the following subsystem malfTinctions: 
failure of the sensing device which controls the liquid level in the evaporator 
(failure could allow the evaporator to go dry or to overfill) ; loss of vacuum; 
slowing or stopping of the urine pump; and rapture of the urine tube. Buildup 
of solids in the evaporator is another cause of failure. However, tests have 
shown that the system can process a 50:50 mixture of urine and atmospheric 
condensate at 2k pounds per day for up to ^0 days with no problem of solid 
buildup. The system design includes two complete evaporators, and after 50 
to kO days of operation the second evaporator is fitted into the system and 
used for the next JO "to k-0 days. The first evaporator is then stored, with the 
urine solids remaining in the used evaporator until the mission is coDipleted. 
An evaporator change requires only the operation of four valves and the transfer 
of the five isotopes from the used system to the new one going into operation. 

Radioisotope Capsule Design 

Five heat soiirces were designed and fabricated by the Monsanto Research 
Corp., Miamlsburg, Ohio, under the direction of the U.S. Atomic Energy 
Commission, Division of Isotopic Development. The AMRL requirements for the 
sources to be compatible with the VD-VF water recovery system are as follows: 



Evaporator unit 



Catalytic-oxidation 
unit 



Humber of sources ^1- 1 

Power (each capsule), watts ...... 73.3 + 1,5 kQ t 2.0 

Operational temperature, °F 100 to 120 2^0 to 28O 

Outer dimensions: 

Outside diameter, in. ....... 1.00 1.00 

Length, in il-,5 4.5 

The capsules were designed and fabricated in accordance with Life 
Support II Heat Source Specification, Monsanto Research Corp. drawing 
No. 1- 15297 (ref. k) . The capsule assembly (fig. 2) consists of two concentric 
cylinders (the clad tube and the liner tube) fabricated to fit at close toler- 
ances at the interface to enhance the thermal conductivity. The capsules were 
designed for a 5-yea'r life to meet long-duration testing and storage. 

95 



The liner tube was fabricated from a tantaliun-lO percent txmgsten material. 
The wall thickness of the liner is O.O3O inch with an outside diameter of 
0.875 inch. The liner is ^.22^1- inches outside length with an internal length 
of ^^-.090 inches and is used to contain the fuel and to provide mechanical 
strength. (Plutoniuni-238, an alpha emitter, requires that a pressure vessel be 
used in this design to contain the resulting helium pressure buildup.) Caps 
were used to seal the liner. 

The clad tube was fabricated from Hastelloy-C and designed to act as an 
interface between the highly reactive refractoiy metal liner and the chemically- 
corrosive environment. The wall thickness is O.O5O inch with an outside diam- 
eter of 0.990 inch; the outside length is k-.k'^Q inches. The capsule was sealed 
with caps. 

Data derived from the stated dimensions and material (tantalum- 10 percent 
tungsten) indicate O.O5 percent creep in 5 years at 1500° P since the stress 
builds linearly from to 22,000 psi diiring the 5 years, and almost all the 
elongation occurs in the last year. Reference 5 indicated that for a 5-year 

2 '58 
lifetime, the PUO2 microspheres are apparently compatible with the 

tantalum- 10 percent tungsten material at temperatures up to 1500° F. 

Refractory metals are incompatible with transition metals when in contact 
at elevated temperatures; however, the diffusion coefficient allows a depth of 
penetration of about 5 mils in 5 years, a rate which is slow enough for accept- 
ability. Higher diffusion rates cannot be tolerated since the tantalum- 
10 percent tungsten liner will lose too much mechanical strength because of 
decreased wall thiclaiess. 

The 0.050- inch- thick wall of the clad tube appears sufficient for use at 
1500° P if only air or inert gas environments are encountered. At 1500° P, 
Hastelloy-C exhibits good oxidation resistance. Air oxidation occurs to the 
extent of 2.5 mils in 1000 hours and 6.0 mils after 5OOO hours at 1832° P 
(refs. 6 and 7). Environmental control must be maintained. Should corrosive 
atmospheres or surroundings be encountered, the heat source would have to be 
located in a shell compatible with both the heat source and the corrosive 
ambient . 



oik 



EEEEREHCES 



1, Metzger, Courtney A. j Hearld, Albert B. j Reynolds^ Bob"by J.; McMullen, 

Bobby G. ; and Thomas, William H. : Low Temperatiire Catalytic Oxidation of 
Waste Water Vapors. AMRL-TR-68-J+8, U.S. Air Force, 1968. 

2. Metzger, Courtney A. : Sterility of Water Recovered From Human Waste During 

Extended Missions Is Attainable Without Post-Treatment j An Engineering 
Approach. AMRI1-TR-7O-I9, U.S. Air Force, Apr. I97O. 

5. Metzger, C. A. : Application of Radioisotopes to Water Recovery Systems for 

Extended Manned Aerospace Missions. AMRL-TR-7O-5I, U.S. Air Force, 1970. 

h. Davis, H, E. ; and Johnson, E. W. : Life Support II Program - Final Report. 
Mi:iM-1757, U.S. At. Energy Coram., Oct. 28, 197O. 

5. Selle, J. E.J and Fitzharris, R. E. : The Conipatibility of ^■5^Pu02 Micro- 

spheres With Refractory Metals and Alloys at 10CX)O C. MIM-I5O2, U.S. 
At. Energy Coram., May 1, 1968. 

6. Anon. : Savannah River Laboratory Isotopic Power and Heat Sources - Quarterly 

Progress Report April-June 1967. Pt. I - Cobalt-60. I3P-1120-I, U.S. 
At. Energy Coram. , July I967. 

7. Hilbom, H. S. , compiler J Savannah River Laboratory Isotopic Power and Heat 

Sources - Quarterly Progress Report January-lfeirch I967. Pt. I - 
Cobalt-60. DP-II05-I, U.S. At. Energy Coram., May I967. 



95 



MANOMETER 

r ■ 1 



URINE STORAGE TANK 




75W ISOTOPE 
(4 REQ'D) 



"\. 



V_. 




^H.O STORAGE TANK 



POTABLE DRINKING WATER 



Figure 1.- VD-VF water recovery system with radioisotopes as energy source. 



96 




0) 
CO 
CQ 

d 

1—1 

m 

U 
I 

N 

U 

•1-1 



97 



PERFORMANCE EVALUATION OF THE THERMAL CONDITIONING UNIT 

By G. E. Allen 
McDonnell Douglas Astronautics Company 

SUMMARY 

The configuration and performance of a thermal conditioning unit used 
during the 90 -day manned test is presented. It includes an evaluation of 
its actual performance and comparison to the design performance. The 
analysis indicates that the unit's actual performance deviated from its 
design performance. However, comfortable temperatures were maintained 
in the living quarters throughout the test in spite of excessive thermal 
loads imposed by the solid amine unit which caused higher equipment room 
temperatures than desired during its operation. High reliability was 
realized throughout the 90 days and no failures required maintenance. 
Areas of improvement in the basic design concepts have been indicated, 
based on experience gained during the test, which would improve the 
operation and efficiency of the thermal conditioning unit. Reconamendations 
are offered which will considerably lower the power required, the quantity 
of primary atmosphere circulated, and the associated noise level of the 
unit in addition to providing individual compartment temperature control. 

INTRODUCTION 

The prime function of the thermal conditioning unit is to maintain tem- 
perature levels suitable for human comfort by removing the sensible heat 
dissipated into the atraosphere. This heat dissipation into the SSS atmosphere 
was derived from occupants, high- temperature heat transfer fluid lines, 
electrical energy, and onboard isotope heaters. The rate of sensible heat 
dissipated from these sources varied as much as 40 percent and thus created 
a requirement for accurate and reliable modulating autonnatic controls. 

In addition to accomplishing its prime function of sensible heat removal, 
the thermal conditioning unit was conceived around strict guidelines which 
limited designing for full optimum performance. These design guidelines 
included: (1) configuring to fit a predesignated minimum volume, (2) providing 
adequate performance over a wide range of cabin pressures, (3) fabricating 
from high-grade commercial or aircraft components, (4) limiting maintenance 
to filter changes, and (5) confining high temperatures resulting from excessive 
heat dissipation to the equipment area. 

UNIT DESCRIPTION 

The thermal conditioning unit configuration (fig. 1) utilized during the 
90- day test consisted of two supply blowers in parallel which drew cabin 
atmosphere through aluminum mesh filters which had 4 ft^ of surface area, 
an acoustical sound trap, and a flow tube for measuring flow rate. The 

99 



discharge from the two blow^ers passed through a noncondensing, extended-fin 
heat exchanger and an eliminator plate before entering the discharge acoustical 
sound trap. Conditioned atmosphere was furnished to the SSS living and bunk 
areas from a pressurized plenum with 19 low- induction- type perforated 
diffusers attached to its underside (ref. 1). Conditioned atmosphere was 
supplied to the equipment area by tw^o rectangular diffusers mounted against 
the acoustical partition between the living and equipment areas. Return 
atmosphere from the living and bunk areas passed through either the acousti- 
cal trap mounted in the door or through the acoustical trap located in the 
partition. 

Coolanol 35 was used in the liquid side of the heat exchanger as the 
coolant fluid. The SSS temperature was controlled by utilizing electronic 
sensors w^ith a thermostat located in the living area approximately 5 ft from 
the deck. The electronic controls consisted of a modified Wheatstone bridge 
with a motor- balancing potentiometer, a low- limit heat exchanger fluid inlet 
controller, and an amplifier- discriminator circuit. The primary signal to 
balance or unbalance the bridge network was provided by the thermostat 
located in the living area. 

A drain pan beneath the heat exchanger and an eliminator plate on the 
discharge side of the heat exchanger were provided to collect any condensate 
which might result from dew points higher than design levels. 

UNIT PERFORMANCE 



Performance of the thermal conditioning unit was monitored by thermo- 
couples installed to measure temperatures within the three areas of the SSS, 
return atmosphere, heat exchanger discharge atmosphere, and inlet- outlet 
coolant fluid. In addition, atmospheric flow through the unit and coolant flow 
through the heat exchanger were measured. This was accomplished by using 
a calibrated flow tube with a differential pressure transducer for the atmos- 
phere and a turbine flowmeter in the supply coolant to the heat exchanger. 
Signals from this instrumentation were fed into preselected channels of a low- 
speed digital system (LSDS) where values were recorded on a half- hour basis 
throughout the test. Magnetic tapes were removed periodically where they 
were processed and reduced into engineering units on an SDS 930 computer. 

Results and Analysis 

The results of the thermal conditioning unit performance were reflected 
in the SSS atmospheric temperature levels maintained during the 90- day test. 
Daily average temperatures for the bunk area, living area, and equipment 
area are shown on figure 2. Examination of these data indicates fluctuations 
of 3. 5, 4, and 9.4 percent. Heat removal rate by the thermal conditioning 
unit heat exchanger varied between 14, 272 and 19, 980 Btu/hr. Total heat 
rejection rates for the SSS were between 22, 800 and 29,500 Btu/hr during the 
test. The difference between the total rejection rate and the thermal 

100 



conditioning removal rate was picked up by cold plates or small extended 
surface compact heat exchangers, including those in the humidity control, 
solid amine unit, and other units. Peak thermal conditioning heat rates 
correspond well with high temperature periods. Causes for variations in 
heating rates and temperature fluctuations will be discussed later. 

Actual Versus Design Performance 

Design and actual performance paraaneters are tabulated in table 1 for 
comparison. Closer control of area temperatures w^as realized during the 
test than thought possible during the design forinulation. However, the upper 
limit on equipment area temperature was exceeded during much of the test. 
This was due primarily to higher than expected (i. e. , higher than allowed for 
during design) heat dissipation within the equipment area. Atmospheric 
diffusion rates in the equipment area were designed to remove 1. 3 Btu/hr- 
ft-^. Heat dissipation densities in this area exceeded 1.65 Btu/hr~ft^ during 
all but three periods during the 90-day test. These three periods occurred 
on test day 14 through 17, 20 through 24, and 81 through 90. Figure 2 shows 
the equipment area temperature dropping from the previous highs during 
these periods. All three periods occurred at a time when the advanced 
(solid amine) C02 removal unit was off line and the baseline (molecular sieve) 
CO2 removal was on line. Examination of the sensible heat loss to the SSS 
atmosphere by each unit indicates the advanced CO2 removal unit increased 
the thermal conditioning load by 6,482 Btu/hr. 

Design heat rejection rate of the thermal conditioning unit never reached 
the design level even though heat dissipation densities for the equipment area 
w^ere higher than expected. Reasons. for this can be traced to the following 
factors: (1) method utilized to achieve comfort control and location of master 
controller and (2) low effectiveness realized from heat exchanger. Tempera- 
ture control was achieved by allowing a master controller, located in the 
living area, to unbalance a laridge circuit. The unbalance caused a modulation 
in coolant fluid temperature supplied to the heat exchanger. Temperature 
modulation of coolant fluid was accomplished by mixing return coolant with 
cold supply coolant in proper quantities. A subraaster sensor in the circuit 
acted as a low-limit controller and prevented achievement of fluid tempera- 
tures which would cause condensation within the heat exchanger. This control 
concept, designed to satisfy comfort conditions only in the living and sleeping 
areas, allowed a single discharge temperature from the heat exchanger. 
Therefore, high heat dissipation in the equipment area had only an indirect 
influence on the control system. Had the master sensor been located in the 
equipment area, control signals would have been generated resulting in 
overcooling the living and sleeping areas. 

The heat exchanger effectiveness achieved during the test was consider- 
ably below that indicated by the manufacturer for this service. Calculations 
show the realized effectiveness to be approximately 0. 2 (i. e., e^ = 0. 2) 
rather than 0.5 as indicated by the supplier. Based on this effectiveness, the 
design heat rejection rate would not have been met at the inlet and outlet 
temperatures specified. It should be noted that standard heat exchangers of 

101 



this type are commonly designed and rated for use >vith water as the coolant. 
Improper techniques were apparently employed in rating the standard unit for 
Coolanol 35 use. [Note: Heat transfer coefficient (h^,) for Coolanol 35 is 
1/10 of that for water (flow and inlet temperature being equal).] 

Some humidity condensation resulted in the heat exchanger, particularly 
during periods of high atmospheric dew point. The condensation occurred on 
the end of the heat exchanger due to an atmospheric leak betw^een the end 
plate and the cold tube return bends. A drain pan was installed to catch the 
water as the leak was discovered after the heat exchanger was installed. 
Condensation from this source averaged 1. 2 lb/day. During the test the crew 
installed a line from the pan drain over to the overflow sump beneath the wick 
evaporator condenser separator. 

The atmospheric filters installed in the return duct to the thermal control 
did not require changing during the test. Spares were carried onboard in 
event clogging occurred. 

CONCLUSIONS AND RECOMMENDATIONS 



The performance of the thermal conditioning unit adequately met the 
mission objectives even though several of the design parameters were 
exceeded. Satisfaction was expressed by the crew with the temperatures 
maintained and noise levels achieved throughout the test. Recommendations 
for an improved thermal conditioning unit would include elimination of 
deficiencies experienced plus a general upgrading of the complete concept of 
temperature control within a confined area. Primary recommendations for 
analysis and testing are outlined as follows: 

A. Achieve at least 70 percent of the sensible heat removal from the SSS 
by use of cold plates located at the source of the dissipation. A large 
power penalty must be paid when removing this heat by circulation of a 
temperature-controlled atmosphere versus a temperature-controlled 
fluid. 

B. Design the thermal conditioning unit to provide individual area tempera- 
ture control. This can be accomplished without individual area heat 
exchangers if a bypass section with bypass dampers is installed with a 
main heat exchanger equipped w^ith face dampers. 

C. Minimize the quantity of primary atmosphere circulated by use of high- 
induction diffusers. Sound generation in a thermal conditioning unit is 
a strong function of the atmospheric flow rate and system pressure. K 
the atnaospheric flow rate can be significantly reduced by only slightly 
increasing the pressure, the sound generation will be lower. 



102 



REFERENCES 



Allen, G. E. , Bonura, M. S. , Thomas, E. C. , and Patnam, D, F. 
Integrated Temperature Control, Humidity Control, and Water 
Recovery Subsystems for a 90-Eteiy Space Station Simulator Test. 
McDonnell Douglas Paper No. MDAC-WD 1241, June 1970. 



105 



-P 0) 



H H 
ni O 



-P 
o 






HOO ON 

• • • 

t— t— t^ 

bO bO bD 
cd cd cd 



ir\KN\o 

• • o 

H H N^^ 

+1 +1 +1 +1 

J- KNt:-CO 
t~- t— t— (Ov 



4J C5 

03 ON 
^.^ H 

o 

u 

s< 

hOi <! 

H 

OJ 



O 



(U (U 

o o 

is; Is; 



o 

ON 
H 



O 

to o 

ft 



+1 +1 +1 +1 



si 
1^ 



o 
o 







o o o 
VDvo m 

<; <3 <; 
o o Q 
S S S 



o 
o 
o 

-4- 




IfN 

H 
O 



H 
O 
O 

o 



u 

o 






H 




-P 
o 

<D 
<U 

H 

•8 

EH 



lOi^ 





[~ 


r 


_j 


>r 


fcO 






"1 










r^!"^§ 


Q£ 












Z O 












1 N. ,,_l U. 


— i/i 














CAB 

sen: 




o 

—1 














o 












o 




SOUND 
TRAP 


LATING 


1 


8 




< 
s 

LU 

X 

u 






:3 sH 1 


1 ^"^ 




t^ 


IIjl 


i 




(> z 


« /^ ^ 










C = 


* Lv 








</) 




> <x 


























s 




A 










UJ 


' ■» 


_j r 


1 
1 








< 








, 


(/> 
















> 


tyo 


i-H 




-J 




^B 


pS 


) 1 




o 

1- 




33 

O 00 


v 


1 




is 




f> 


I 








z 










o 




1 1 
















o 




o 










_J 




R < 










< 




Se 










s 














oc 


f> 






UJ •< 


} 1 


1 








X 

1- 


URNER 














^ 1 

X 


,. 


-J 








o 












t— 


_ Z 










o = 


z q: 










4 


lEsE 










c 


J a 


: < 


c 















105 



UJ 



< 
m 

OL 

S 

UJ 

H 

oc 
o 



<n 




(Jo) 3iiniVH3dlAI3i iiOiVinWIS 



106 



PERFORMANCE OF THE CO2 CONCENTRATORS 

By E. S. Mills and T. J. Linzey 

McDonnell Douglas Astronautics Company 

SUMMARY 



The performance of the CO2 concentrator system consisting of the 
advanced baseline solid amine system, the backup molecular sieve systena, 
and the emergency lithium hydroxide- Genaini CO2 removal unit was satisfac- 
tory. The average CO2 concentration in the cabin over the 90-day test tinae 
averaged approximately 5 mm Hg rather than the intended 4 mm Hg, pri- 
naarily because of the problems with adjusting the solid amine concentrator. 
The solid amine unit was used for CO2 control during the majority of the first 
81 days of the test. The solid amine required a significant amount of naain- 
tenance; although this was not unexpected, considering the state of develop- 
ment. The backup molecular sieve CO2 concentrator unit was used for CO2 
concentration when the solid amine was inoperative. The molecular sieve was 
operated during test days 14 through 25, 33, 34, and 81 through 90. The solid 
amine unit was operated part of test days 18 and 19 to check repairs being 
made. The major problems with the solid amine were maintaining the correct 
percentage of water in the beds during absorb and desorb cycles and keeping 
the inlet air at the correct temperature for the bed conditions. The nnajor 
mechanical problems were a sticking valve that required manual cycling, a 
solenoid valve sticking open, and the clogging of the condensed water drain in 
the exhaust condenser. When adjusted correctly, with the proper water 
balance in the beds, the unit maintained the CO2 cabin concentration at the 
specified level. 

The performance of the molecular sieve CO2 concentrator was satisfac- 
tory, serving the role of backup when needed. Only minor problems were 
encountered, a leaking valve, short bakeouts required after starting up from 
standby conditions, and a nonfunctioning zero-g separator. The negative 
pressure device used with the LEM elbow zero-g w^ater separator did not 
function properly. Before the start of the test, this was replaced by a collec- 
tion tank installed downstream of the separator to collect the condensed water. 

Operation of the Li OH unit was not required during the test. 

INTRODUCTION 



The function of the CO2 concentrator is to maintain the partial pressure 
of CO9 at approximately 4 mm Hg and to provide pure CO2 for processing in 
the Sabatier reactor for atmosphere recovery. This function is provided by 
an advanced solid amine system with a molecular sieve unit as backup and a 
Li OH CO2 removal unit for emergencies. 

107 



The solid amine concentrator is an experimental unit built specifically 
for the 90-day test frona off-the-shelf hardware. It utilizes a weak base 
amine ion exchange resin, IR-45, for CO2 absorption. It was built by 
Hamilton Standard under contract to NASA-LRC. 

The molecular sieve CO2 concentrator was used for CO2 concentration 
during the I968 60-day NASA/MDAC chamber test, rebuilt, and updated. 
The major changes to the unit are 

A. Replacement of the two four-way electric air diverter valves 
isolating the silica gel beds with four three-way pneumatic valves. 

B. Addition of an Apollo suit compressor for circulation of cabin air 
through the unit. 

C. Replacement of the cycle timer with a more positive snap action 
switch, cam timer. 

D. Addition of a filter upstream of the CO2 compressors to remove 
any dust coming from the beds, 

E. Complete rearrangement of component locations to obtain access 
for maintenance and part replacement and to meet installation 
space limitations. 



DESCRIPTION OF OPERATION 



Solid Amine 

The basic components of the solid amine CO2 concentrator units are three 
separate beds packed with solid amine ion exchange resin particles, two circu- 
lation fans (one redi;indant ) , two condensing heat exchangers, two compressors 
to pimp CO2 to the accumulator (one redundant), a boiler and superheater, two 
water pumps (one redimdant), timer and cycle control unit, manifolds, and 
sequence control valves. A schematic of the -unit is shown In figure 1. 

Dehumidified cabin air from the humidity control outlet is drawn into the 
unit by the circulation fan. The air then passes through a filter and a con- 
denser/heat exchanger to condition it to the desired temperature and relative 
humidity. The air then enters the absorbing amine canister(s) where the 
CO2 contained in the air stream is removed. The purified air is then 
returned to the cabin through the second condenser /heat exchanger. This 
heat exchanger cools the air and condenses the water removed from the 
absorbing bed during the absorption reaction. This water is passed to the 
water storage accumulator. The desorption of the amine beds is accom- 
plished with superheated stream. Water is pumped from the storage accu- 
mulator to a two-stage water boiler. Heat is supplied from the Coolanol 35 
heating fluid circuit. The steam generated in the boiler /superheater at 



108 



ZlOiS^F is passed through the amine bed where it condenses on the arnine 
resin. The resultant heat and water release the CO2 from the amine 
particles. The CO2 is then reabsorbed downstream in the bed. After 
sufficient steam is condensed in the bed and the bed temperature is 
elevated, the CO2 is eluted from the canister. The CO2 is then pumped 
to the CO2 storage accumulator. The temperature sensor in the bed dis- 
charge line senses when the steam breaks through, indicating the end of CO2 
desorption. A diverter valve then diverts the bed effluent (steam and water) 
to the cabin through the second condenser /heat exchanger. Either two- or 
three-bed operation is possible. In the three-bed mode, two beds are 
absorbing with the third on desorb. 

Molecular Sieve 

The basic components of the molecular sieve unit are two silica gel beds 
in parallel, a heat exchanger, a circulation blower (Apollo suit compressor), 
a heat exchanger, two molecular sieve beds in parallel, a sequence timer, 
manifolds, and sequence control valves. A condenser and zero-g water 
separator are provided to remove water vapor from the silica gel beds 
desorption air stream. A schematic of the unit is shown in figure 2. 

Function of the unit is as follows: cabin air is drawn through the 
adsorbing silica gel bed where the moisture in the air is removed to a dew 
point of -50 to -70 °F. The flow then enters the circulation blower and passes 
through the heat exchanger cooling it to 40 to 50 "F, The cool, dry air then 
passes through the adsorbing molecular sieve bed where the CO2 is removed. 
Approximately 80 percent of the dry, C02-free gas is discharged into the 
cabin. The remaining gas is passed to the desorbing silica gel canister 
which has been heated to approximately 300 °F with hot Coolanol. This dry 
gas flow picks up the water being driven off the beds by the heat and carries 
it to the condenser and separator where it is collected and passed to storage. 
The desorbing molecular sieve bed is being regenerated, heating to 300 "F 
with the hot Coolanol and evacuating with a vacuum pump (or external vacuum 
system if not necessary to collect the CO2). The vacuum pump pumps the 
desorbed CO2 to an accumulator for storage. To remove the cabin gas from 
the canister voids at the start of the desorb cycle, the gas is pumped back to 
the cabin through the adsorbing nnolecular sieve bed for a few minutes. This 
insures pure CO2 when flow is switched to the accumulator. After 30 min- 
utes of desorption, cold Coolanol is pumped to the desorbing beds to cool 
them before cycling to the adsorption cycle. After 45 minutes, the timer 
sequences the valves to divert the cabin flow through the regenerated beds 
and place the beds now requiring regeneration on desorption cycle. Hot 
Coolanol will then flow through the desorbing beds and the cycle is repeated. 
The time for a complete adsorption, desorption, and cooling cycle is 90 
minutes. 



Liithium Hydroxide 

For emergency use, in the event both the primary and backup C02 con- 
centrator units were inoperative and repairs could not be completed before 



109 



the CO2 concentration reached excessive levels, a lithium hydroxide removal 
unit was installed. It had the capacity of 28 man-days CO2 removal, 

PERFORMANCE DURING THE 90- DAY TEST 



The cabin atmosphere CO2 concentration during the 90-day run is shown 
in figure 3. The abnormal operation peaks are numbered for reference. The 
significant events are as follows: 

Test Day 

3 Main valve on bed 1 did not automatically cycle. Crew had to 
rotate valve manually. This occurred approximately 200 times 
until day 14. 

13 Peak (1). CO2 removal efficiency reduced. It appears bed 2 was 
excessively wet, due to delays in performing the above noted manual 
valve sequencing. Attempts to dry bed 2 failed. 

14 Unit shut down. Molecular sieve started up. Drying of solid amine 
beds accomplished, 

18 Bed 1 isolated because of valve problem. It was suspected that 
valve sticking caused bed 2 to overwet. Operation on beds 2 and 3 
initiated; molecular sieve shut down, 

19 Peak (2), Solid amine could not maintain the cabin CO2 concentra- 
tion within acceptable limits. Molecular sieve placed in operation, 

25 Problern. in solid amine traced to shifting of inlet air thermocouple 
reference junction by +15°F. Instrumentation recalibrated. 
Molecular sieve shut down. Solid amine restarted, operation 
satisfactory. 

26 Peak (3), Solid amine not maintaining CO2 level. Evaluation 
to showed steam generation rate too low. Water filter element 
28 changed, rate increased. Operation satisfactory. 

33 Peak (4). Pneumatic compressor on solid amine valve actuation 
system failed. Solid amine shut down. Molecular sieve started up. 

34 Molecular sieve performance marginal. Bakeout performed. Unit 
performance satisfactory after bakeout. Restarted solid amine 
unit, with gaseous nitrogen supplied to unit, replacing air compres- 
sor function. 

45 Peak (5). Solid amine could not maintain the required CO2 levels, 
and It was suspected bed 2 was excessively wet. Bed 2 dried by "dry" 

46 desorb technique. Operation improved. 

110 



48 Condensate was observed to be flowing from the condenser outlet. 
Investigation revealed the condenser was full of water. The drain 
line was plugged. This caused excessive wetting of bed 2. The 
physical layout of the system allowed water trapped in the heat 
exchanger to drain back frona the heat exchanger inlet to the dis- 
charge line from bed 2, and into bed 2. Therefore bed 2 received 
excessive water. The water line was disconnected and backf lushed 
through the heat exchanger, 

58 Peak (6). High cabin CO2 level. The heat exchanger again was 

plugged, causing excessive wetting of the beds. The heat exchanger 
was blown out again, beds "dry" desorbed. Performance improved. 
(This occurred approximately every 2 to 3 days until end of 
operation. ) 

65 Peak (7). Water filter changed allowing greater steam generation 
rate. Improved performance. 

74 Plug fell out of amine bed 3 canister allowing several pounds of 

amine resin to leak out of the canister. Hole plugged. Performance 
marginal. 

76 Peak (8). Solid amine could not maintain required CO2 level. Cycle 
time shortened from 13 to 12 minutes. 



80 



Cycle time reduced to 11 minutes in attempt to improve per- 
formance. 



81 Peak (9). Bed 3 performance negligible. Bed 3 shut down, bed 1 

activated. Cycle tinae increased fromi 11 to 12 minutes. No effect. 
Cycle time increased to 13 minutes; bed 1 was very difficult to 
cycle manually. Unable to obtain required performance in bed 1. 

81 Unit shut down at 1, 533 hours. 

81 Molecular sieve started. 

90 Test terminated. 

One significant factor is the thermal balance of each unit. The require- 
ment for heat supply and cooling can constrain vehicle design. The typical 
thermal balance of the molecolar sieve and solid amine units is shown in fig- 
ures h and 5^ respectively. 



CONCLUSIONS AND RECOMMENDATIONS 



The solid amine unit demonstrated its effectiveness for maintaining 
cabin CO2 concentration. The problems encountered can be easily solved, 
by design improvements. The water balance problenn can be overcome by 



111 



placing humidity level detectors in the beds and automatically or manually 
controlling the steam generation rate to each bed. The problem of flooding 
can be eliminated by redesign of the condenser to allow filter changing. The 
solid amine contributes a greater latent and sensible thermal load to the 
atmosphere than desired. Optimization of operation and hardware will 
undoubtedly improve this penalty. The 90-day test was the first time that 
a solid amine CO2 concentrator unit operated in a manned test. 

The performance of the molecular sieve during the test was satisfactory. 
For futxzre operation, a more efficient water separator may be used as well as 
more efficient molecular sieve material. 



112 




™ Ir?2 <d COMPRESSOR 
TANK ^ 



CABIN 
AIR 



t t I i i \ 



CABIN AIR 
FROM POT.I>l 
WATER UNIT 




N„ PRESS. (TO ACCUATE VALVES) 
COOLING 

Figure 1.- CO2 concentrator - solid amine unit. 



HEAT 



NG 



CABIN 

AIR 

FROM 

HUMIDITY 

CONTROL 

UNIT 



HEATING 

4_i 



„ COOLING TO CABIN 
t I ■ f 



SG-1 



CONDENSER 



SEPARATOR 



— r- 



SG-2 



% 



ptj^ MS-l | -CJ^ 



BLOWER 



TT 

COOLING 



TOCO2 
ACCUMULATOR 



COOLING 
± k 



HEAT 



-jl(^y |EXCHANGER 



VACUUM 
PUMPS 



El PRESSURE ACTUATED 
59 VALVE 



4^ — m- -^-m 



HEATING ,, 



1 



COOLING 
±± 



m m 



TO 
,, CABIN 



r\ 



TO SPACE VACUUM. 



SSS WALL 
U^ CHECK VALVE 

Figure 2.- CO2 concentrator - molecular sieve unit. 



ISJ SaENOID 
^ VALVE 



115 




> 
< 

Q 



ui 



(D 
ft 
3 

a> 
u 
a, 

• p-4 
-M 

(U 



fe d 



c 
o 

u 
as 
U 



CO 

Qi 

a 

• rH 



O 00 (D <« CM O 

r- 

(Bh mm) 3UnSS3Ud IVIlUVd 301X010 NOSUV3 



I2h 



LATENT HEAT 

INPUT (WATER IN AIR) 

3,940 BTU/DAY 



FlECTRICAL 
POWER 
52,000 BTU/DAY 



AVERAGE HEAT 
INPUT HOT 
COOLANOL 
79.600 BTU/DAY 



i 



TOTAL AVERAGE HEAT 
INPUT 135,540 BTU/DAY 



T 



AVERAGE LOSS TO 
CABIN-SENSIBLE 
26,740 BTU/DAY 



AVERAGE OUTPUT TO COLD 
COOLANOL (INCLUDING ~75 PERCENT 
ELECTRICAL LOAD) 
108.800 BTU/DAY 

Figure 4.- Thermal balance of molecular sieve unit. 



ELECTRICAL 
POWER 
61,200 BTU/DAY 



AVERAGE 
BOILER HEAT 
INPUT-HOT COOLANT 
174,000 BTU/DAY 



i 



TOTAL AVERAGE HEAT 
INPUT 235,200 BTU/DAY 



T 



AVERAGE LOSS 
TO CABIN 



SENSIBLE 
LATENT 
35% ELECT- 
RICAL LOAD 



AVERAGE CONDENSER OUTPUT TO COOLANT 

87,500 BTU/DAY 
ELECTRICAL LOAD 

39,750 BTU/DAY 

127,250 BTU/DAY TO COOLANT 



60,000 BTU/DAY 
26,500 BTU/DAY 
21,450 BTU/DAY 

107,950 BTU/DAY 



Figure 5.- Thermal balance of solid amine unit. 



115 



OPERATIONAL CHARACTERISTICS OF THE INTEGRATED 
SABATIER/ TOXIN BURNER UNIT 

By J. F. Harkee 

McDonnell Douglas Astronautics Company 

SUMMARY 



Operation of the Sabatier reactor during the initial 30 days of the 90 -day 
manned test was somewhat complicated by catalyst poisoning caused by trace 
quantities of Freon-113 (TF) appearing in the carbon dioxide. Operation 
returned to normal after replacing the catalyst and adding a charcoal trap to 
remove the contaminant from the carbon dioxide. The Sabatier unit produced 
about 550 3Jb of water during the test. The average water production rate for 
the last 60 days was ^i-.jS lb/day. The reactor converted over 95 percent of the 
hydrogen processed to water. The toxin burner operated normally throughout 
the test. 



INTRODUCTION 



The Sabatier functions to recover oxygen from the carbon dioxide exhaled 
by the crew. The carbon dioxide is reacted with hydrogen from the electro- 
lysis unit at a temperature of about 700°F in the presence of a catalyst to pro- 
duce water for the electrolysis unit, methane (exhausted), and heat. 

The toxin burner oxidizes hydrocarbons, methane, and carbon monoxide 
to carbon dioxide and water vapor. This reaction also occurs at a temperature 
of 600° to 700°F in the presence of a catalyst. Because of the low concentra- 
tion of oxidizable material, heat must be added to maintain reaction conditions. 

The integration advantage is to utilize the heat produced by the Sabatier 
to support the toxin burner operation thereby reducing spacecraft power 
requirements. 



DESCRIPTION OF UNITS 



The primary components of the Sabatier unit are the CO2 pressure regu- 
lator, H2 and CO2 mixture control valves, Sabatier reactor, reactor pressure 
control valve, and a zero-g condenser/water separator. 

The toxin burner unit consists of a regenerative heat exchanger, an elec- 
tric heating elenment, a temperature controller, and a catalytic (Hopcalite) 
reactor. A schematic of the units is presented in figure 1, 



117 




The Sabatier obtains CO2 at accumulator pressure. The CO2 flows through 
the pressure regulator, which obtains a pressure reference from, the H2 supply. 
The regulated CO2 then flows through a control valve under critical flow con- 
ditions. The H2 flows directly to a separate critical flow-control valve. The 
two gas streams naix downstream of the control valves and then flow into the 
reactor. The reactor is a jacketed cylinder; the inner cavity contains the 
nickel-on-kieselguhr catalyst. Air from the toxin burner regenerative heat 
exchanger flows through the jacket to remove reactor heat. The catalyst bed 
is normally operated at a pressure of from 460 to 505 mm Hg and a temper- 
ature of 500° to 750°F. The CO2/H2 mixture reacts to form methane (CH4) 
and steam. 

The product gases containing some excess CO2 and a small amount of un- 
reacted H2 leave the reactor and flow through the zero-g condenser/ separator 
and then a conventional backup condenser where the steann is condensed and 
separated as water. The CH4 and unreacted gases then flow through the 

cri tical- flow reactor jpressure-control valve to the Space Station Simulator 
(SSS) vacuum subsystem. The zero-g condenser/separator Is approximately 8 in. 
long by h in. vide by I-I/2 in. high and is divided into two compartments by a 
partition of porous metal. Chilled water wets one surface of the porous plate. 
The reaction gases flowing along the opposite surface are cooled and the steata 
condenses and wets the porous surface. The condensed water will then transfer 
through the porous plate into the cooling water by capillary action and a con- 
trolled pressure difference. Product water flawing through the plate increases 
the displacement of a negative-pressure device^ triggering the magnetic latching 
of a reed switch which activates the proper valving to allow conrpressed CO2 to 
displace the water into the electrolysis water storage tank. The backup con- 
denser collects any water it recovers in a small accumulator. A float switch 
in the accumulator activates a positive displacement pianp which also discharges 
the condensate into the water storage tank.- 

The toxin burner obtains SSS air from the discharge side of the thermal 
control unit blowers at a rate of about 90 ft^/hr. The air is forced through 
the regenerative heat exchanger, where it is preheated by the exit gas stream. 
The gas then flows through the cooling jacket of the Sabatier reactor where it 
absorbs a portion of the reaction heat (and likewise cools the reactor). The 
gas then passes through the electric heater, where the gas temperature is 
increased to the proper oxidation temperature (predetermined by the temper- 
ature controller). The gas then traverses the catalytic reactor bed to the hot 
side of the regenerative heat exchanger and then exits to the cabin, 

OPERATION OF SABATIER REACTOR : 



During the initial part of the test, many valve adjustmients and stabilization 
of reactor temperature with the starter heater were required. The mainten- 
ance activity during the test is sunnimarized on table 1, The unexpected atten- 
tion requirements were partially caused by the frequent changes in hydrogen 
sources and pressures affecting H2/CO2 mixture ratios. At the middle of the 
third week, it became apparent that the reactor was not operating in a normal 
manner. The temperature profile in the reactor shifted toward the aft end of 

118 



the reactor, and a tendency for the reaction to be blown out the end of the 
reactor was experienced. Poisoning of the catalyst was suspected. Since 
electrolysis produces almost pure hydrogen, it seemed likely that the poison 
was entering with the carbon dioxide. On the 16th day, the reactor was 
switched to commercial grade bottled CO2 to observe if the catalyst would 
"clean up" and, if not, to ascertain the degree of catalyst deterioration. 
Samples of CO2 from the onboard accumulator were analyzed to determine 
what trace contaminants naight be present. Contaminants found, in addition to 
the expected O2 and N2, were ethanol, acetone, and Freon-115 (TF). A brief 
review of the literature indicated (ref, 1) that nickel-hydrogenation catalyst 
could be poisoned by compounds containing sulfur or halogen groups by a 
mechanism of tying up the "active" sites of the catalyst. Freon-115 contains 
both chlorine and fluorine atoms of the halogen group. The next step was to 
determine if significant amounts of the Freon-115 would be thermally decoraposed 
\mder reactor conditions. Mr. David Grana of NASA liRC arranged to operate its 
Sabatier reactor with similar Freon concentrations ajid conditions. IMC quickly 
reported that Freon decomposition was found to be in excess of 80 percent, with 
no halogens being foimd in the exhaust gas stream, but with significant concen- 
trations of halogens being present in the product water. 

The source of the Freon- U.5 is attributed to the cleanup following a 
failure of a Coolanol line during the unmanned SSS baseline test. Freon was 
used as a final wash to renaove all traces of the Coolanol. Though the SSS was 
ventilated for several days before the repeat of the unmanned baseline test, it 
is believed that trace quantities remained absorbed on surfaces within 
the simulator. The trace quantities that desorbed during the test were 
removed by the CO2 concentrator units. 

Reactor operation on bottled CO2 did not significantly improve. Reaction 
during this period remained in the aft end of the bed with occasional "flame - 
outs". The reactor operated to the 22nd day on bottled CO2, when a charcoal 
trap was placed in the cabin CO2 delivery line. Gas samples taken down- 
stream of the charcoal trap indicated that the charcoal was effectively removing 
all organic trace contaminants. Operation' continued without improvement 
utilizing CO2 from the molecular sieve until the 28th day when it was decided 
to replace the catalyst. It is interesting to note here the past history of the 
catalyst. This catalyst was used for 15 days 'before the 60-day manned test, 
52 days during the 60-day manned test, about 25 days in bench testing prior to 
the 90-day manned test, 8 days during the preliminary unmanned and manned tests, 
and 28 days during the 90-day manned test, giving a total operational history of 
about 128 days. No sign of deterioration was observed prior to the unmanned 
baseline test. The reactor was down the 28th and part of the 29th day while the 
crew replaced the catalyst and leak tested the reactor and subsystem. The used 
catalyst was placed in a No. 2 tin can and sealed while awaiting the next sched- 
uled pass-out. The new catalyst (Ni-OlO^l-T-l/S", Ifershaw Chemical Company) was 
placed in an open aluminum pan until the exothermal reaction with the oxygen- 
rich atmosphere was' complete to avoid any crew handling accidents while loading 
the reactor. After completion of loading and sealing the reactor, it was leak 
checked by pressurizing it to 50 psia with nitrogen and immersing in water. 
After assembly into the subsystem, the unit was evacuated to 5 psia and pre- 
heated to 5000 F to demonstrate gas-tight integrity at elevated temperatures. 

119 



The reactor was then heated to 550° F and slowly purged with hydrogen to 
activate and reduce the catalyst. The unit was then started using routine 
procedures. 

Operation with the new catalyst was smooth and required little attention 
by the crew. Water production increased from an average- of 2. 7 lb/day for 
the initial 30 days to 4. 38 lb/ day for the remaining 60 days. These values as 
well as the daily water production quantities are shown in figure 2. This fig- 
ure also includes the 25. 2 lb of water lost through the exhaust. Hydrogen utili- 
zation is shown on figure 3 and carbon dioxide utilization is shown on figure 4. 

Sonne crew attention was used to rennove the reactor insulation during the 
period when the toxin burner unit was intentionally turned off (to compensate 
for the decrease in rcav-l^x ,_ooling capacity). 

The reactor was shut down for partial periods of four of the last 60 days 
of the test because of interruption of supply gases. The charcoal trap had a 
capacity of about 120 in of charcoal and a useful life of about 11 days. 
Biweekly testing of the CO2 both upstream, and downstream of the charcoal traps 
was accomplished. However, the shifting aft of the reaction within the 
Sabatier turned out to be the most sensitive method of determining when the 
charcoal needed replacing. During the short period of time (approximately 
20 nainutes) required to change the charcoal, CO2 bypassed the trap to naain- 
tain reaction. For a period of 6 to 24 hours after changing the trap, the 
reaction remained stable in the aft end of the reactor before returning to the 
normal position. 

On test day 87, methane concentration in the SSS increased significantly. 
The Sabatier, a producer of nnethane, was then reduced in operating pressure 
from about 530 torr to 480 torr, well below cabin pressure. The SSS methane 
concentration then leveled off and began to decrease. However, the reactor 
pressure control valve was in the fully open position to maintain the pressure 
at a lower than cabin level. On the 88th day, the Sabatier was shut down and 
leak tested. A gross stress corrosion failure along the nainimuna stress axis 
of a 90-degree bend in the exhaust line between the reactor and the condenser 
was found. The corrosion was attributed to hydrogen chloride and hydrogen 
fluoride in the exhaust. The line was replaced by the crew, and the reactor 
operated normally for the remainder of the test. 

Daily analyses of the Sabatier exhaust gases were made and quantities 
recorded. Figure 5 shows the res\£Lts of the activity and provides information 
relative to the use of these exhaust gases as propellants in a resistojet atti- 
tude control system. It should be recognized that the exhaust may include some 
nitrogen. All nitrogen entering the system is unreacted as it passes through 
the system and exhausts with any unreacted CO2. 

Operation of the zero-g condenser/ separator was not completely initiated 
until the 14th day of the test; cold Coolanol flow was maintained through the 
condenser throughout the test, the product condensate being allowed to drain 
into the backup condenser. When the negative pressure device was energized, 
it pumped gas through the porous plate of the condenser. Repeated attempts 
to stop the gas breakthrough were tried on test days 16, 29, 30, and 50. 

120 



Efforts included various adjustments in cooling flow. The negative pressure 
device was actuated 42 times during this period. Replacement of the condenser 
was delayed to avoid long-term exposure of the crew to any spillage of Coolanol. 
The condenser was replaced on test day 81. Inspection of the initial condenser 
indicated discoloration and corrosive pitting of the porous plate, probably 
caused by hydrogen chloride and hydrogen fluoride resulting from the thermal 
decomposition of Freon and absorbed in the product water. 

The new unit worked in a normal raanner until day 83 when the negative 
pressure device becarae stuck about a quarter of the way down on the "down" 
stroke. The negative pressure device had automatically pumped 31 strokes of 
water at this time. The unit was freed by actuating a momentary switch in 
parallel with the piston proximity switch. This method of actuating the nega- 
tive pressure device was used for the remaind-er of the test. Post-test inspec- 
tion disclosed that the piston was at the bottom of the stroke, indicating that 
the piston proximity switch might be inoperative. 

Typical operating conditions of the zero-g condenser during the run on 
the Coolanol side were 38°F inlet and 54°F outlet. The vapor side tempera- 
tures were 163°F inlet and 90°F outlet. The unit apparently had inadequate 
effectiveness to completely remove the water from the exhaust gas. 

OPERATION OF TOXIN BURNER 



Operation of the toxin burner throughout the test was routine and without 
operational probleras, as previously noted on table 1. Burner temperatures 
were adjusted between 560OF and 730°F throughout the last 60 days of the test 
to investigate variations in cooling effect on the Sabatler reactor. The toxin 
burner was turned off from days 68 through 81 to observe changes in carbon 
monoxide, methane trace contaminants, and microbiological activity. 

On day 68, while turning the toxin unit off, the crew observed a powder 
deposit in the area of the discharge-to-cabin vent. A sample of this material 
was collected and passed out for chemical analysis. Preliminary results 
indicate the material to be mainly chlorides of aluminum, copper, iron, 
nickel with minor amounts of silicon, magnesium, chromium, titanium, 
manganese, and boron. It would appear that the material resulted from the 
thermal decomposition of Freon in the toxin burner to forna chlorides and 
probably fluorides with the Hopcalite catalyst and the stainless steel and 
aluminum components of the unit. Since this material has an insignificant 
vapor pressure, it is not known how the material could transport through the 
regenerative heat exchanger to the vent. Dust carried along with the process 
gas stream seems the only obvious method. 

In light of the catalyst poisoning experience in the Sabatier and the 
chloride deposits, it can be suspected that the Hopcalite was adversely 
affected by the Freon. The extent and time history of the catalyst degradation 

are not knovm; if the degradation occurred during the initial part of the test, 
the requirement for a toxin burner can be questioned. If toxin bxiraers are 
required, methods of protecting the catalyst from poisoning must be developed. 

121 



Correlation of carbon monoxide and methane concentrations in the SSS 
with toxin burner operation is not conclusive. Carbon monoxide is com- 
pletely oxidized at room temperature by Hopcalitej therefore, correlation 
with it should be nnore pronounced. During the period the toxin unit was off, 
carbon monoxide concentration increased from about 16 to 26 ppm. When the 
unit was returned to operation, the concentration decreased over a period of 
9 days to a level of 18 ppm. This seems to indicate the unit did function to 
affect the CO level; however, this type of correlation could possibly be 
expected with an unheated catalyst. The strongest evidence of the ability of 
the unit to oxidize methane is exhibited during the last 3 days of the test after 
the repair of the Sabatier exhaust leak. Hydrocarbon concentration at this 
point reached a level of 60-ppm heptane equivalent, and decreased to a level 
of 50 ppm at the end of test. Cabin leakage was minimal during this period; 
therefore, little washout effect of contaminants occurred. This significant 
lowering in hydrocarbon level tends to indicate the toxin unit maintained some 
effectiveness throughout the test. However, the general gradual rise in 
hydrocarbon levels in the atmosphere during the test, which is mainly due to 
an increase in methane concentration, may indicate that a gradual reduction 
in capacity was occurring. Daily values of cabin hydrocarbon concentrations 
are shown in figure 6. 



CONCLUSIONS 

A. The Sabatier /toxin burner units performed as expected after catalyst 
poisoning problems were resolved. 

B. The Sabatier produced twice the wfeight of it and the toxin burner in 
water and contributed a considerable amount of thermal energy to 
support operation of the toxin burner. 

C. Future Sabatier reactor development should include provisions to 
protect the catalyst from poisons. 

D. Quicker methods of initiating reactor operation such as a glow-plug 
type starter would be a worthwhile convenience. 

E. Future development of negative pressure devices should tend towards 
a short-stroke configuration and utilize a separate pumping device to 
move the water to the storage reservoir. 

REFERENCE 

1. Perry, John H, : Chemical Engineers' Handbook, Fourth Edition, page k-12. 



122 



TABLE I 
MAINTENANCE ACTIVITY 



SUBSYSTEM 


MAINTENANCE ACTIVITY 


SPARES USAGE 


HOURS 


TOXIN CONTROL 


NONE 


NONE 


NONE 


SABATIER 


REPLACED FUSE AND PRIMED WATER PUMP 


FUSE 


1.5 




REPLACED C02 FLOW TRANSDUCER* 


TRANSDUCER 


0.3 




CLEARED WATER FROM METHANE PUMP* 




0.2 




INSTALLED CHARCOAL TRAP IN C02 LINE* 


CHARCOAL COLUMN 


3.0 




CHANGED CATALYST 


CATALYST 


7.0 




CHANGED CHARCOAL* 


CHARCOAL 


2.5 




CHANGED ZERO-G CONDENSER 


CONDENSER 


1.5 




ATTEMPTED TO UNSTICK NEGATIVE PRESSURE 








DEVICE 




0.6 




REPLACED LEAKING TUBE AT REACTOR OUTLET 


12 IN. TUBING 


2.0 
18.6 



*OUTSIDE ACTIVITY 



125 



o 
o 

ui S 

si 



ly 



CD 
< 
CO 




12k- 



o 

3 
O 

o 
a. 



a: 

UJ 

I- 
< 




(ai) U31VM 



125 



o 

< 

N 



Hi 

8 

a 




(ai) NioouaAH 



126 



o 

< 
N 



liJ 

9 

X 

o 
o 



< 

o 




be 

•iH 



o 


>« 


O 


"> 


o 


U) 


lO 


CM 


d 


h" 


lA 


M 



(ai) ^00 



127 



c/> 



o 
o 

< 
LU 

tr 

< 

< 
CO 




Ava/S3iow-ai 



128 







7 














V 


hfc 








CO 






\ 








en 






1 








>- 






/ 














f 








< 






1 








z 






1 








< 






v 








z 






\ 








o 






\ 


L 






CD 








V 






< 








A 












1 






o 








/ 






o 








/ 






ce 








/ 






> 








1 












1 






X 






1 






UJ 






1 






z 








I 












1 






■■■i 








% 






-J 








v 






1 








X 






z 








N^ 






o 








^v 


^ 



















CD 
OO 



CD 



s 



s 


>■ 
< 

1— 






t/» 


CO 


^ 


1— 


o 

1*4 


o 






CTk 







s 



§ 



o 



§ 






S 



(ZO) 3NVid3H Wdd 

'NoiivyiNBONOo NoaiiV3 oyaAH 



129 



EERFOEMANCE OP A SOLID- AMDSE CAIBON DIOXIDE CONCENTRATOR 

DtlRIMJ A 90-DAy MABKEID TEST 

'S^ Harlan F. Brose 
Hamilton Staxidard 
Division of United Aircraft Corporation 

aaid 

Rex B. Martin 
NASA Langley Research Center 

SUMMARY 

A carlion dioxide (CO2) concentration system ■which utilized a regenerahle 
amine atsorhent was used in the 90-day Dmnned test. Hamilton Standard utilized 
surplus flight hardware from the Manned Orhiting Lahoratory project to meet the 
cost, schedule, and manned-test constraints. The system design was "based oh 
test data provided hy MSA Research Corporation. The design provided for limited 
automatic operation with manned override capability. The successful operation 
of the unit during the 90-day test estahlishes solid amine as a feasible CO2 
absorbent with certain advantages over a molecular sieve COg control system. 

The principal advajitages demonstrated in the 90-day test are the ability of the 
sorbent material to operate with humid influent gas, with good performance at 
low CO2 pressures, and with the ability to desorb CO2 at ambient pressiire and 

higher. 

IBTTRODUCTIOH 

The affinity of Linde Molec^ilar Sieve for water (H2O) in preference to 
carbon dioxide (CO2) is axi inherent deficiency of this sorbent when utilized 
for CO2 removal since the influent gas must be dehydrated. Consequently, 
research has been sponsored to investigate sorbents potentially having more 
desirable characteristics than Molecular Sieve. The MSA Research Corporation 
(MSA), under contract to the HASA Langley Research Center (LRC) found that the 
weak-base amine ion-exchange resins showed promise as regenerable CO2 sorbents. 

(See ref. 1.) Subsequent research by MSA under contract to LRC derived system- 
design information specifically for amberlite IR-^5 ion-exchange resin from 
Rohm and Haas Company (ref. 2). 

This resin is durable and is widely used in liquid purification processes. 
It has been found useful in the removal. of such weak acids as 002? although 
relatively little is known about such resins for the absorption of gases. The 

151 



earliest references to ion-exchange resins as potential low-concentration CO2 
gas sorbents were for anesthesiology (ref. 3) and submarine atmosphere applica- 
tions (ref. k). 0!he aresin provides additional advajiteiges over Molecular Sieve 
in that desorption is at cahin pressure rather than at near vacuum and that 
elimination of compressors for pumping the COg is potentially possible. The 

latter aspect will he discussed further herein. 

The important characteristics of this sorhent are as follows: 

(1) It is spherical in shape with a mesh size of 16 to 50. 

(2) It has a density of 59 to kj) lb/ft5 with ko- to 45-percent water con- 
tent and 35- "to iiO-percent void space. 

(5) The heat capacity when 20-percent H^O "by weight is 0.^ Btu/lb-°F} 
and the heat capacity when dry is 0."3l4 Btu/n3-°F. 

(k) It is insoluble and inert in strong acids (except nitric acid), con- 
centrated alkalis, and coimnon organic solvents. 

(5) It is unaffected by prolonged exposure to water at 212 F. 

(6) Porosity, swelling, and moistiire-holding properties are dependent 
primarily upon the degree of polymer cross -linking. Swelling is also directly 
related to water content. 

This steam-desorhed amine sorhent was selected for the COg concentrator 
system in the advanced integrated life support system study (ref. 5) because of 
consistently high ratings for the applications considered. Thus, when certain 
flight -development prototype hardware became available from the Manned Orbiting 
Laboratory (MOL) in mid-1969 and when the state of amine technology at the time 
was considered, it was desirable and feasible to have Hamilton Standard design 
and fabricate an e2?perimental amine sorbent system for the 90-day manned test. 

SYSTEM DESCRIPTION 



The system design assumed that certain MOL hardware, for example, three 
canister and valve assemblies, heat exchangers, and so forth, would be avail- 
able for use in the system. Steam regeneration has several advantages for this 
sorbent and was plajined as the mode of desorption for the system. The most 
significant advantages are that no heating coils are required in the canisters 
and that cycling hot and cold coolant is not required. Laboratory investiga- 
tions were conducted by MSA to determine certain system design- and operation- 
parameter information specific to the MOL Environmental Control System canister 
and to this particular three-bed design. 

The system design that evolved is shown schematically in figure 1. Three 
canisters were used in a three-phase cycle which was considered base-line 

132 



operation; however, a two-eanister mode was also incorporated. In the three- 
canister mode, each canister is desorbed , during one phase or l/5 of the cycle 
and ahsorhs during two phases or 2/3 of the cycle. The complete cycle lasts 
^5 minutes. Each canister is charged with 7-5 pounds of amine containing 
15-percent water hy weight. A void expansion space, which was 50 percent of 
the canister volume, was allowed between the top retaining screen and the bed 
for resin expansion since the resin expands about 1 percent per 1-percent 
increase in water content up to about ij-5-percent water by weight, which is the 
saturation condition of the resin. The water content of the resin cycles 
between 25 percent by weight at the end of desorption to about 10 percent at 
the end of absorption. 

Process air from the chamber humidity control system at ^5° F to 50° F 
and 40° F dewpolnt is passed through either of two redundant fans at 25 ft5/min 
and then through a heat exchanger to condition the air to the desired tempera- 
ture and relative humidity. The airflow divides and passes throtigh two canisters 
connected in parallel, where the CO2 is absorbed by a weak chemical bonding on 

the amine resin and the purified air is then returned through a second heat 
exchanger to the cabin. This heat exchanger cools the air and condenses mois- 
ture that was removed from the sorbent since the sorbent contains the water 
condensed from the previous steam desorption. 

Each canister undergoes desorption in turn in the following manner: Steam, 
at cabin pressures, is generated in a two-stage finned-tube-in-shell steam 
generator. The superheated steam flows into the canister, condenses on the 
resin, the resin is heated, and the CO2 is displaced and is reabsorbed down- 
stream. This thermal mass-transfer zone passes through the canister smd 
canister-void-space air, then humid CO2 and finally steam are eluted from the 
canister. Since the CO2 is recovered at 12 psia or higher if desired, the com- 
pressor requirements are reduced from those of a molecxilar sieve system. If an 
acc-umulator pressure of 30 psia is acceptable, it would be possible to eliminate 
compressors completely and use steam pressure to compress the CO2 into the 
acciimulator. The pressure is limited because IR-k-^ will degrade at temperatures 
over about 250° F. 

During the first half of the desorption cycle, canister-Toid-space humid 
air at about 85° F is flushed from the canister. As CO2 begins to elute from 

the bed, a flow-rate change is sensed, and the effluent is diverted to a com- 
pressor which stores the CO2 at a pressure suitable for the oxygen-reclamation 

system. The effluent temperature rises during this period, and at a tempera- 
ture of 170° F, the steam breaks through and the flow is diverted back to the 
system outlet heat exchanger where the gas is cooled and moisture is condensed 
and returned to the system water accumiilator. For rediandancy, two compressors 
are installed in parallel. 

Water is recycled within the system, however, a net water loss may occur 
because of the loss of water vapor in the collected CO2 and if a net difference 

exists between the system outlet vapor concentration and the inlet vapor con- 
centration. An external water soxirce was connected to the water accumulator. 

135 



The accumiilator has high and low level switches which automatically control its 
refilling. 

Two water-metering p;jmps were installed between the water accumulator and 
the steam generator. The water-pumping rate was selected so that water would 
he supplied to the steam generator at a rate siofficient to desorh a canister 
within the selected desorption period of 15 minutes (l/5 cycle) with ahout 
2 minutes to spare. A hack-press\ire regulator was located between the effluent 
diverter valre and the COg compressor to maintain the sorhent hed at the proper 
pressure to give a steam temperature of ahout 200° F while CO2 is being pumped 

to the accumulator. A second diverter valve was located in the steam line to 
divert steam to the system condensing heat exchanger after the bed is heated 
sufficiently to desorb the CO2 loaded on the bed. 

Controls were provided for fully automatic operation for either three- or 
two-canister operation. For redundancy a completely timed mode of operation 
was also provided in addition to the flow and temperature controls for desoirp- 
tion. For flexibility during the 90-day test, all control set points were 
manually adjustable. 

Photographs of the front and rear concentrator system are shown in fig- 
ures 2(a) and 2(b), respectively. The size of the unit is approximately 
4 ft X 4 ft X 2 ft. The weight is about 60O pounds. Because of the use of 
commercial hardware, a frame made of grating to save program schediale and cost, 
and the fact that the two-canister mode was adequate (as will be discussed later), 
the size and weight of the concentrator system can be reduced significantly for 
a flight system. 

SAFETT CONSIDERATIONS 

System Out gas sing 

Most materials and parts not approved for use in a manned test with a non- 
standard atmosphere were enclosed in an aluminum box of O.06O gauge, spotwelded 
on five sides. The information displays and controls were mounted on the front 
of the panel drawer of the box. This entire box assembly and the remaining 
items containing materials not approved for use in a manned test with a non- 
standard atmosphere were placed in a 75 ft^ oven, heated to 130° P, and outgassed 
for three days prior to final system assembly. The hydrocarbon (referenced to 
pentane) outgassing rate for the three-day period was I8 ppm for the 75 ft5 
enclosed space for the first day, 8 ppm for the second day, and h.^ ppm for the 
third day. 

Sorbent 

Four samples of the sorbent were submitted to NASA Manned Spacecraft Center 
for testing (ref. 6). The results of these tests concerning flash and fire 

I5I+ 



point, flame -propagation rate, odor, and carbon monoxide (CO) and total-orgeinics 
outgassing are summarized as follows: 

(1) JR-h^ passes flamma'bility criteria 

(2) IR-45 passes odor criteria 

(5) IR-^5 passes total-organics criteria 

(h) IR-45 Is borderline on CO outgassing, but steam exposure reduces 
concentrations sufficiently for pass rating 

EERFOBMAHCE ERIOR TO 90-DAY TEST 

Testing of a single-cajiister assembly at MSA indicated that a canister CO2 
loading of up to 2.5 percent of dry-bed weight or 0.15 pound of CO2 per canister 

cycle was feasible if a proper water balance could be maintained in the canister. 
It was known from earlier testing that a 20-percent-by-wel^t bed water loading 
was ideal for GO2 absorption and that higher and lower water loading would give 
less CO2 absorption. 

Maintaining proper bed water loading was indicated in single-canister 
testing at MSA as the most importaxit problem in this design, and this fact was 
confirmed when the system was tested at Heimllton Standard. Thus, if the exact 
quantity of steam condensed in the bed on desorption and partially absorbed by 
the bed was not removed or if excessive water was removed during the subsequent 
diylng CO2 absorption period, the beds would progressively get wetter or diyer, 
respectively, and less than optimum performance would result. If the beds 
became slightly wetter each cycle, the CO2 removal performance would approach 

zero. If the beds became slightly dryer each cycle, the CO2 removal rate would 

stabilize at about 9-6 lb/day at a ^ mm Hg pressure input level with a 50-minute 
absorption cycle. !Ehe optimum removal rate was determined to be about 12 lb/day 
at an average of 20 percent by weight water loading. As a result, a canister 
inlet air temperature was selected that would cause the beds to stay on the 
average on the dry side since only a 9 lb/day CO2 removal rate was required for 

the system. Furthermore, the selected temperature of 80° F and hQ° F dewpolnt 
gives adeqiiate drying margin to prevent the canisters from becoming wet because 
of nominal change in coolant flow and inlet air condition. 

Absorption performance of the resin is shown In figiire 5« These data were 
taken during the dry, stable operation of the system which resixlted in a 
9.6 lb /day CO2 removal capacity. The curve shows the combined absorption of 

two canisters and the effluent temperature profile of a single canister. It 
can be seen that most of the CO2 absorption takes place during the first 

10 minutes of its two-phase absorption cycle. However, the remaining 20 minutes 
are required to complete the bed drying prior to another desorption. 



155 



A canister cycling from desorption to absorption . is hot and moist but dries 
rapidly during the first 5 minutes Of the absorption cycle because the process- 
air temperature rises rapidly as it passes through the canister and thus obtains 
a significant water-vapor capacity. This evaporation cools the bed rapidly and 
makes drying much slower for the remainder of the cycle. ¥ith a given quantity 
of sorbent, the ratio of bed length to diameter (f«2) was unfavorable for an 
ideal optimization of flow rate and cycle time. Ihe flow rate and cycle time 
were selected in order to obtain the required capacity; thus, an operation less 
efficient than would be possible by designing a bed for a specific application 
resulted. 

The desorption characteristics are shown in figure h. The effluent flow- 
rate change used as a switch point for CO2 collection and the steam break- 
through with the corresponding temperature rise indicating completion of CO2 
desorption are evident. The change in effluent flow rate immediately after 
the diverter valve switches to CO2 collection results because the back- 
pressure regulator increases bed pressure. 

Approximately 300 hours of investigatory tests were conducted at Hamilton 
Standard. These tests were concluded by a 3-day continuous operation acceptance 
test. During the acceptance test, the unit operated fully automatically with 
no adjustments being made. Average CO2 performance for the three days was 

9.6 lb/day at a 4 mm Hg CO2 pressure in the air inlet. 

Because of the chemical nature of the CO2 sorption, TR-k^ has a more favor- 
able isotherm for low CO2 pressures than Molecular Sieve. A test was conducted 
to determine the performance of the system at a 1 mm Hg CO2 pressure. The sys- 
tem removed 5 lb/day at this condition. 

The tests conducted on the amine system for the Langley Research Center 
and McDonnell Douglas Astronautics Company 90-day test were oriented only to 
obtain acceptable performance from the system for the four -man crew require- 
ment. Adequate data to determine optimum cycle time, bed geometry, air flow, 
and so forth, were not possible due to schedule and cost constraints. It 
appears that significantly greater performance could have been obtained with a 
shorter cycle (fig. 3) and a ratio of bed length to diameter of about 1 instead 
of 2, since the bulk of the absorption occurs in the first 10 minutes. It also 
appeared from these data that two-canister operation may be more desirable. 
During the 90-day test, it was necessary to operate in a two-canister mode. 
The performance data verified that the two-canister mode was generally more 
desirable for this particiilar system than the three-canister mode. 

FERPORMAIFCE DURING 90-DAY TEST 

The amine CO2 concentrator operated successfully as a system experiment 
during the 90-day test. This result is evident when the extremely short 
schedule (8 months) to bring a laboratory concept to prototype manned test 
hardware is considered. Ih.e unit was operated for 71 days. Figure 5 shows the 

136 



G02 pressure level as a function of test days. The concentra,ted GO2 purity 
during the test was 94 to 98 percent. Table I indicates the malfunctions which 
did occur during the test and the corrective action taken. For all malfunctions, 
the crew was ahle to take corrective action without requiring materials from 
outside the chamber. From this table, the inrportance of the attention given to 
redundancy and alternate operating modes in the design of the unit is apparent. 



TABIiE I.- MAIOTNCTIOWS OF AMnSE CO2 COHQENTRATOE DURING 90-DAy TEST 



Test days 


Ifelfunction 


Cause 


Corrective action 


3 to 10, 81 


Bed 1 rotary valve 
sticking when reposi- 
tioning porting for 
atiBort 


Excessive friction hetweeti 
rotaiy-valve plate and 
seals 


Lubricating plate and manual 
operation not successful; 
finally went to two-bed 
operation 


2k, 81 


Tfeit operating tempera- 
tures 15° F higher 
than the Indicated 
readings 


Unit thermocouple reference- 
junction set point had 
changed 


Compensated for discrepan- 
cies between actual and 
indicated temperatures 


29, 62, 6h, 
66, 67, 71, 
72, 73 


Water accumulator dry 
or overflowing 


Water-supply solenoid valve 
sticking in both the open 
and close positions 


Cycled with panel override 
switch; finally replaced 
solenoid valve 


h&, 58, 60, 
63, 75, 77, 
79 


Condenser drain line 
plugged 


Deposits of material in line 


Iteriodically purging the line 
with pressurized nitrogen (Hg) 


60 


Noise in coarpressor 1 


Unknown 


Switched to compressor 2 


71 


28-volt "power on" 
light not energized 
(unit running) 


Burned-out hulh 


Replaced bulb 


74, 80 


Amine material suad 
steam leaking fi-om 
hole in hed 3 


Epoxied patch loosened 


Plugged hole (amine material 
not replaced) 


3^^ 


Fan would not start 


Unknown 


Switched to fan 2 



A complete posttest analysis of the unit will be conducted. In addition 
to the analysis of the malfunctioning components and an analysis of materials 
compatibility, a postacceptance test will be conducted to determine the amine 
material condition. 

Periodic manual adjustment of coolant flow to the unit was required during 
the test. For flight hardware or new long-duxation test hardware, fully auto- 
matic control of airflow and inleti-drylng conditions should be incorporated. A 
direct measure of bed-moisture conditions is necessary in order to properly 
control inlet process-air drying capacity, and this improvement must be con- 
sidered in future hardware. 

Information derived during the 90-day test and from a posttest analysis of 
the hardware will greatly enhance the capability of designing a solid-amine 
CO2 concentrator for future manned tests. 



137 



CCMCLUDinG RIMAJRKS 

The use of existing flight-development hardware provided the lead time 
necessary to fabricate a system suitable for the 90-day test; however, this 
hardware posed some problems in its adaptation to the amine-system design. A 
more favorable canister configuration would have resulted in a reduced steam 
flow rate and a significant increase in the absolution efficiency. As a resxolt 
of the 90-day test, it is obvious that direct sensing of the sorbent moisture 
condition is mandatory and that this information shoiild be used to control the 
drying capacity of the inlet process air automatically. In addition, ion- 
exchange cleanup in the water and steam circuit is needed and may show a very 
significant trace-contaminant-removal capability for this system. !Ehe use of 
waste or isotope heat is felt to be significantly advantageous with this sys- 
tem concept. 

All malfxmctions of the system that occurred in the 90-day test were hard- 
ware development problems that are judged to be amenable to a reasonable develop- 
ment effort. Perhaps the problem that may require the most development and 
testing is the hardware design to "hold" the sorbent during cyclic swelling and 
contracting without causing sorbent agglomeration. 



REFEREINCES 



1. Tepper, F.; Vancheri, F.| Samuel, ¥. ; and Udavcak, R.: Development of a 

Regenerable Carbon Dioxide Removal System. Contract HAS 1-5277^ MSA 
Res. Corp., Jan. 15, I968. (Available as HASA CR-6657I.) 

2. Anon.: Amberlite IR-45. IE-1^-68, Rohm and Haas Co., Juae I968. 

3. Smart, Richard C; and Derrick, William S.: The Carbon Dioxide Absosrption 

Properties of Ion-Exchange Resins. Anesthesiology, vol. I8, 1957^ 
pp. 216-222. 

k. McConnatighey, ¥. E.j Crecelius, S. B.j and Crofford, ¥. N., Ill: Removal 
of CO2 From Submarine Atmospheres by Amine Resins — A Feasibility Study. 
imL Rep. 5022, U.S. Navy, Nov. 1957- (Available from DDC as AD li^9 09^.) 

5. United Aircraft Corp.: TraqLe-Off Study and Conceptual Designs of Regenera- 

tive Advanced Integrated Life Support Systems. NASA GR-lh^d, 1970. 

6. Anon. : Procedures and Requirements for the Flarmnability and Outgassing 

Eval-uation of Manned Spacecraft Nonmetallic Materials. D-NA-0002, 
Manned Spacecraft Center, I968. 



138 




u 
o 

O 

o 
o 

o 
o 

a; 

s 

■»-> 

O 
O 

•iH 

1^ 





CD 


> 


^ 








1 




(P 


s< 


h 


0« 



?n 




•r-l 




fe 


s: 









H 









< 




a: 










159 



ELECTRONiC 
CONTROL BOX 



;;f^i^i 



DISC VALVE 
PNEUMATIC 
DRIVE PISTON 



WATER PUMPS 




CANISTERS 



(a) Front view. 



CO2 COMPRESSORS - 



FANS 



INLET AIR 

HEAT EXCHANGER - 



• CONDENSING 
HEAT EXCHANGER 



-BACK PRESSURE 
REGULATING VALVE 




FLOWMETER 



T — BOILER AND 
il '\ ■ SUPERHEATER 

.it ■■ 

CO2 AND STEAM 
DIVERTER VALVES 



WATER 
ACCUMULATOR 



(b) Rear view. 
Figure 2.- Amine CO2 concentrator. 



lij-O 



(do) 3«niVU3dW3i iN3mdd3 



o 

00 



o 



s 



o 



S 8 



o 
o 



s 



Q 
00 



o 





























V 


k, 














i 






\^ 




^ 






lU 














^^>N^ 






oc 














^S 


, 




D 
















^^ 




H 
















Ak 




< 
















\ 




QC 
















\ 




BC UJ 
















\ 




Lu a. 
















\ 




V) UJ 


1 














% 




1 














1 




z"- 














1 




<t- 


/ 


















2 


















t:i = 






















/ 


- 















— 




C/3 Ui 

1 


/ 






I 












^ 


/ 


1 




V 












y 


7 








\^ 












/ 










r' 


> 










/ 










H 

S g 


"^^ 


\ 


/ 


^ 










3S 1^^ 




\ 


/ 












"iS z? 

go: ooc 
l--°- OQ 
>-o £5 




^ 


/ 














y 
















y 














wo C< 


^^^ 


















I ^ 


p*" 




















^^^^ 




■ 
































._ 


. .- 


— ■ — ' 






.- — - 


"^ 









M 

UJ 
(- 

z 
i 

LU 

s 



§ 

■^ 

u 

% 
u 

0) 
CO 






(— < 
o 
>» 
o 

O 
OS 

CD 

CD 

I 



in 



ii X? 



o 
v< 
a 

o 

u 

O 
CO 

% 

a 
.1-1 

S 



I— I 
u 
>. 
a 

o 

CQ 

•^ 

1 



CO 

•1-4 



o 

CO 






(Bhujui) 3unSS3Ud ^OO lN3mid3 



lill 



(do) 3yniva3diAi3i iNamdda 




n en r- 

(3AiiviniAinD gid) iN3mdd3 ayos3a 



Xi 
C 

B 

CO 



Xi 

a 

•iH 

s 

U 



CD 

O 

1— « 

i 

o 
to 

ID 



O 

a. 

a 
o 
•1-1 

U 
o 

CO 
(0 

•f-l 

s 

< 



•iH 



1^4-2 






m 



« s 
p. g 

<N ' — 

o 
u 



o 



,o 

00 



E2 

2 



.o 



o 



m 



H 



in 



^ 




« 


B 


ft 


a 


CN> 




O 





o 



o 
in 






,o 



o 



in 



in 



t> 


^.^ 


t/a 


o 


(» 


s 


s 


a 


ft 


a 






CM 




o 





o 



o 

CM 



IS 





!^ 






O 






-M 






a 






!h 






■M 






fl 






01 






o 


*'-*«w 




n 


• 




o 




rn 


CM 


3 


IH 


,9 


V) 


<J 


u 


P* 


d 


o 


pS 




.s 


& 


S 






HH 




(Tt 


H 


0) 
J3 


■ri 




■iJ 


<u 




<*-( 


> 




o 


o 




(U 


CQ 




o 

a 


^ 

^ 

3 




^1 


U 




o 


cu 




V, 


o 




a> 


Fi 




a 


-M 




-M 


crt 




CQ 


J3 




O 


■«>> 




-M 






>. 






rt 






•o 






>> 






•M 






0) 






f3 





•rH 



lk3 



ANALYSIS OF TRACE CONTAMINANTS 
By P. P. Mader, Ph. D. and J. K. Jackson 
McDonnell Douglas Astronautics Company 

SUMMARY 

Analysis of atmospheric samples for the presence of trace contaminants 
was conducted by MDAC to ensure the continued health and safety of the test 
crew. Analysis was done by chromatograph on direct samples and concen- 
trated samples obtained by freeze- out techniques to determine the presence 
of organic compounds. The direct samples indicated the presence of as many 
as nine organic contaminants although none were present at levels approaching 
critical values. The concentrated samples, taken weekly, indicated as many 
as 23 compounds, most of which occurred at very low levels. Major trace 
contaminants included methane, as high as 290 ppm at the end of the run; 
carbon monoxide, which varied from 10 to 27 ppm; and Freon TF, which 
reached peak values as high as 11.6 ppm. Methane and carbon monoxide are 
most probably the metabolic products of the crewmen. The Freon TF is a 
cleaning solvent which was used before the test, apparently leaving residuals 
that maintained the cabin concentration throughout the test. 

Inorganic compounds were measured by wet chemical analysis on samples 
taken daily. Compounds detected included total aldehydes, which maintained 
a fairly stable concentration of about 0. 35 ppm during the test, and ammonia 
during some periods, reaching levels of 2 to 3 ppm. During toxin burner 
operation, the presence of ammonia was frequently accompanied by trace 
amounts of oxides of nitrogen (about 0. 1 ppm). Sulfur dioxide, hydrocyanic 
acid, hydrogen sulfide, chlorine, hydrochloric acid, and phosgene were tested 
for and not found at any time during the test. 

Tests run on CO2 removed from the cabin by the raolecular sieve and solid 
amine units indicated increased concentration of Freon TF over the cabin 
levels. This resulted in locating an activated carbon filter in the CO2 line to 
remove this contaminant during the test. 

Tests on catalyst from the Sabatier reactor and a white powder found at 
the outlet of the toxin burner indicated heavy concentrations of halogens. This 
apparently resulted from catalytic decomposition of the Freon TF and may 
have caused a significant loss in catalyst effectiveness in both units. 

INTRODUCTION 



During the 90- day operation of the Space Station Simulator (SSS) and the 
short- duration manned and unmanned test runs which preceded it, analytical 
support was provided by determining the composition and daily fluctuations of 
trace contaminants. A daily search was instituted in which representative 

1^5 



air samples were withdrawn from the SSS and analyzed. Both sampling and 
analytical procedures depended on whether the tests pertained to organic or 
inorganic compounds. 

Additional analyses carried out by the laboratory pertained to: 

A. Composition of constituents in CO2 gases between concentrator and 

Sabatier unit. 

B. Analysis of Sabatier catalyst and toxin burner catalysts. 

C. Purity of hydrogen, oxygen, and CO2 tanks. 

D. Composition of exit vapors of the Sabatier reactor. 

E. Analysis of reclaimed water for compliance with potability standards 
proposed by the Ad Hoc Committee of the Space Science Board of the 
National Research Council. 

The present report describes the types and quantities of inorganic and 
organic compounds found in the SSS and the analyses of toxin burner and 
Sabatier catalysts. 

Particular attention was directed to specific compounds (see table 1), 
which have been reviewed and to which pretest planning had assigned contin- 
gency and abort levels. Many of these levels were established upon the 
recommendation of the Panel on Air Standards for Manned Space Flights of 
the National Academy of Science. 

INORGANIC CONTAMINANTS 

Conventional wet chemical analyses of the cabin air were performed 
daily for ammonia, sulfur dioxide, oxides of nitrogen, and aldehydes. Twice 
a week tests were run for hydrocyanic acid, hydrogen sulfide, chlorine, 
hydrochloric acid, and phosgene. These test data as well as those obtained 
during the 4- day unmanned and the 5- day manned tests which preceded the 
90- day test are tabulated in tables 2 and 3, 

During the 90-day manned operation of the SSS, the VD-VF unit and the 
wick evaporator system were alternately used for water recovery. It was 
desired to obtain data on the effect of the open-loop wick evaporator on the 
normal contaminant level measured in the cabin air, and whether a correlation 
existed between the observed contaminants such as anxtnonia and oxides of 
nitrogen. Additionally, information was desired on the effects of the toxin 
control unit on formation and buildup of contaminants in the SSS. 

During the unmanned and manned test periods preceding the 90- day test, 
the space cabin air was almost free of contaminants. Analyses conducted after 
the start of the 90-day test also showed the absence of all inorganic compounds, 
as seen in table 3, with the only exception being the aldehydes which started 

11^6 



with a low value of 0. 04 ppm, and soon increased to 0. 2 to 0.4 ppm. They 
remained at this level throughout the entire test. Initially, neither ammonia 
nor oxides of nitrogen were detected in the cabin air, regardless whether the 
VD-VF or wick evaporator system was in operation. This lasted until test 
day 52, when the presence of ammonia was detected at about 0. 5 ppm. 
Simultaneously with the appearance of ammonia, traces of oxides of nitrogen 
(less than 0. 1 ppm) were found. This reinforces a previous indication that the 
catalytic burner may cause oxidation of ammonia to oxides of nitrogen. 

On test day 57, after the wick evaporator had been in operation for 
12 days, the further feeding of the wick was stopped, and the VD-VF unit was 
placed in operation. In spite of this, the ammonia concentration in the 
chamber increased during the following few days, reaching a peak at about 
2. 8 ppm. This may be due to the fact that after starting to dry the wick, 
more ammonia was formed from the wick deposits and released into the cabin 
air. After several days without wick operation, the ammonia concentration 
in the atmosphere returned to zero. 

The effects of the toxin control unit with regard to the ammonia conver- 
sion can be seen from the data of test days 68 through 82. During this time, 
the unit was inoperative. In this entire period no oxides of nitrogen were 
found in the SSS although the amount of ammonia that was present in the cabin 
atmosphere was similar to the previous period. Soon after the toxin burner 
was activated, the oxides of nitrogen again appeared, reaching a maximum of 
about 0.15 ppm. 

ORGANIC CONTAMINANTS 



Daily gas samples were withdrawn from the cabin air by the syringe and 
needle technique. Analyses were carried out with the two gas chromatographs 
calibrated for 120 organic compounds at two temperatures and with two column 
packing materials. Ten organic compounds including carbon monoxide (which 
was measured with a Lira Infrared Analyzer) were identified and quantitatively 
determined. Figures 1 through 5 show the identification and concentrations of 
these compounds for each test day. The concentration ranges were: Freon 
TF, 1 . 6 to 11.6 ppm; acetone, 0.06 to 2.39 ppm; toluene, 0.05 to 0.15 ppm; 
ethyl alcohol, 0.35 to 1.49 ppm; dichloroethane, 0.08 to 0.25 ppm; methyl 
ethylketone, 0. 05 to 0. 27 ppm; 2-ethylbutanol, 0. 14 to 0.43 ppm; 2-ethyl 
hexanol, 0. 1 to 0.68 ppm; methane, 110 to 290 ppm; and carbon monoxide, 
7 to 27 ppm. 

The horizontal bar between test days 68 and 82 represents the time 
interval during which the toxin burner was not in operation. After test day 68, 
the carbon monoxide level (fig. 5) increased from about l6 to 26 ppm. When 
the toxin burner was reactivated, the level was gradually reduced to 17 ppm 
at the end of the test. 

With regard to methane (fig. 5), it was noted that the concentration of 
this hydrocarbon increased from approximately l60 to 245 ppm when the 
toxin burner was inoperative. However, no decrease in the methane level 



was observed when the toxin burner was placed in operation again. A further 
increase resulted between samples taken on days 87 and 88. This was caused 
by a leak in the exhaust line of the Sabatier reactor which vented exhaust 
gases into the cabin, thereby adding to the methane level in the cabin air, 
since thernethane concentration in the exhaust was approximately 50 percent. 
Replacement of the faulty tube stopped this venting and the corresponding rise 
in methane level. 

With regard to the other organic compounds plotted in figures 1 through 4, 
no specific trends were noticeable. Measured concentrations were relatively 
low^ in all cases. 

Freeze-out samples were collected on a weekly basis by passing 60 liters 
of cabin air into a stainless steel trap which was immersed in liquid nitrogen. 
The noncondensable gases were returned to the cabin, while the remainder was 
condensed in the stainless steel trap and was analyzed by chromatograph. A 
total of 23 organic compounds could be identified by the use of the concentrated 
samples, as compared to nine compounds w^hen noncondensed samples were 
used. 

Most of the chromatographic peaks exhibited by the large -volume samples 
could be identified. Those from the pre-test checkout runs are shown on 
table 4> and from the 90 day test on tables 5 and 6. A few unassigned minor 
peaks remain to be identified. Efforts in this direction are being undertaken. 

, It may be of interest that three compounds, methylisobutylketone, 
n-amylalcohol, and n-valeraldehyde, were present only during the unmanned 
5-day run. These compounds were not found during any of the manned runs, 

ANALYSIS OF CARBON DIOXIDE 



The carbon dioxide desorbed from molecular sieve or solid amine sorbant 
after removal from the SSS atmosphere was then processed in the Sabatier 
reactor. 

Since the CO2 originated in the cabin air the possibility existed that other 
contaminants may be present in the CO2 stream leaving the concentrator. It 
was important to know the comiposition of the gas stream reaching the Sabatier 
unit because the catalyst, upon which the Sabatier reaction is based, may be 
gradually deactivated or completely destroyed by the presence of undesirable 
contaminants. 

Analysis of the CO2 showed the presence of Freon TF at an average 
concentration of 8. ppm, and acetone and ethyl alcohol at low concentrations. 
Carbon dioxide, oxygen, and nitrogen coxnprised 98 to 100 percent of the total 
gas flo-w. 

An analysis of the Sabatier catalyst, which consists mainly of metallic 
nickel deposited on kieselgur as carrier, was carried out. This sample was 
removed from the reactor by the crew on test day 29 and passed out of the 
chamber after a long period of intermittent operation had led to the conclusion 



that catalytic activity had been lost. It was found to contain large amounts of 
chlorides and fluorides. Although there were no samples of unused catalyst 
available, it is probable that the identified halogens came from the Freon TF 
present in the CO2 initially supplied to the reactor. Comparisons between 
unused and spent catalyst will be made. The efficiency of the catalyst may 
have been impaired or completely destroyed by continuous contact with 
halogens from the Freon TF. 

A metal analysis of the catalyst by atomic adsorption showed nickel and 
silicon as major components. Present in trace araounts were boron, phos- 
phorus, manganese, iron, magnesium, and lead. These elements may be 
assumed to be normally present in the catalyst. 

After the test crew replaced the spent nickel catalyst with new material 
on test day 29, an activated carbon filter was placed in the CO2 line. Analyses 
of samples taken downstream of the carbon filter showed that Freon TF as 
well as the two organic compounds mentioned above had been completely 
removed. This point was subsequently monitored periodically for the balance 
of the test and the carbon filter replaced to prevent further contamination of 
the catalyst by Freon. 

A white powder at the outlet of the toxin burner was collected at the end 
of the test. Analysis of this powder showed an extremely high concentration 
of chlorides. The presence of fluoride was not specifically identified because 
it was obscured by the high chloride content. Analysis of the powder by 
atomic adsorption spectroscopy showed the following major constituents: iron, 
aluminum, nickel, and copper, besides several minor trace constituents. 
These major metallic constituents may have originated in the Hopcalite 
catalyst or from attack of the tubing or heat exchanger downstreara of the 
catalyst bed. 



149 



TABLE I 

MAJOR ATMOSPHERIC CONTAMINANTS IN SSS 



CONTAMINANT 


ACCURACY 


NORMAL 
OPERATIONS 


LOWER END OF 

CONTINGENCY 

OPERATIONS 


ABORT 
LEVEL 


ALLOWABLE LEVEL 
SPECIFIED BY 

NAS/NRC 
COMMITTEE 


CO (ppm) 


t2.0 


12.0 


100 


200 


X 


CO2 (mm Hg) 


io.4 


4.0 


8 


* 




HYDROCARBONS (ppm) 


±2.0 


4.0 


60 


300 




NH3(ppm) 


il.O 


4.0 


75 


150 




ALDEHYDES (ppm) 


±0.005 


1.0 

■ 


15 


25 




SO2 (ppm) 


io.25 


as 


7 


12 




HjS (ppm) 


±1.0 


1.0 


IS 


30 




mO)^ (ppm NOj) 


io.i 


0.5 


1.5 


IS 




Oj (ppm) 


to.ooi 


0.03 


0.15 


1.5 




CHLORINE (ppm) 


-0.04 


ai 


0.7 


1.5 




CYANlbES (ppm) 


ti.o 


1.0 


3.0 


15 




PHOSGENE (ppm) 


to.2 


0,07 


0.15 


1.5 




ETHANOL (ppm) 


Ua 


2.5 


300 


1,500 




TOLUENE (ppm) 


to.2 


0.5 


30 


300 




2-ETHYL BUTANOL (ppm) 


to.2 


1.0 


20 


60 




N-BUTANOL 


to.2 


1.0 


15 


150 


X 


2-BUTANONE 


ta2 


xo 


30 


300 


X 


CHLOROFORM , 


ia2 


0.5 


7 


70 


X 


DICHLOROMETHANE 


to.2 


Z5 


40 


700 


X 


DIOXANE 


to.2 


1.0 


IS 


'ISO 


X 


ETHYLACETATE 


to.2 


4.0 


60 


600 


X 


2-METHYLBUTANONE 


ta2 


2.0 


30 


300 


X 


TR ICH LOROETH YLENE 


to.2 


1.0 


15 


150 


X 


1,1,2-TRICHLORO; 












1 .2,2-TRIf= LUOROETH ANE 












AND RELATED CONGENERS 


io.2 


20 


ISO 


1,500 


X 


FORMALDEHYDE 


». 


0.(» 


0.15 


3.0 


X 


DICHLOROLACETYLENE 


— 





DETECTED 


0.1 


X 


VINYLIDENE CHLORIDE 


•- 


2.0 


10 


25 


X 



*>60 (3 MIN), 60 TO 40 (10 MIN). 40 TO 30 (30 MIN). 30 TO 20 (60 MIN), 20 TO IS (48 HOURS) 



150 



m 



-J o 

QQ 

< o 

I— 2S 

UJ 

X 

a. 
O 



UJ 


























2 


























O 
















CD 








CD 


to 
















O 








^ 


o 




















































a. 


























o 
















CD 








CD 


^ 
















o 








CD 


CM ,-^ 












CD 








CD 


^ S 
















• 

CD 








• 

CD 


o 


























■MM- 


























■ —J 






















—i 


























CVJ ^ 


to 










K— 




CD 








CD 


3= q; 
LU 


LxJ 

1— 










to 




CD 








CD 


Cl_ 


>- 

< 

o 

1 

o 










1— 














HCN 
PARTS 










>- 
< 
O 




• 

CD 








• 

CD 




uu 










O 














.^^ 


■^^ 










UJ 














— — 


z 










2?" 














y^ »^ 


< 










^ 














:hyde 
alue: 




1 


, 


Si 


8 

• 


< 


CM 
1— 1 

• 


OO 

i-H 


I—I 

i-H 

• 


CM 

• 


1 

1 


8 

• 










O 


CD 




CD 


CD 


CD 


CD 




<:> 


-J -J 


























< ^ 




















































S' 


C3 


o 


o 


O 


CD 


CD 


O 


CD 


o 


CD 


to 




O 


o 


o 


<=> 




CD 


CD 


CD 


CD 


C3 


o 


«?■ 




O 


o 


CD 


CD 




C3 


CD 


CD 


CD 


CD 


CD 


Z 




O 


C3 


O 


CD 




-O 


O 


O 


O 


CD 


CD 


cr\ 




CD 


O 


O 


CD 




CD 


CD 


CD 


<Z> 


CD 


CD 


^ 




• 

o 


• 

CD 


• 


« 

CD 




CD 


• 

CD 


• 

CD 


C5 


O 


^ 




o 










IxJ 

Q 




ITS vO 


r— oo 




O 

ON o t:: 


£^ 


^ Si 


Ci Ci 




^ £Q ci ^ £2 ^ 




'sr 


''a- 


■^ 


^!T 


'ST 




'a- 


'a- 


\r\ 


\rs 


iTk 


m 



151 



TABLE 3 







ATMOSPHERIC TRACE CONTAMINANTS DURING 90-DAY TEST 








TEST 








ALDE- 










PHOS- 


DATE 


DAY 


NH3 


S02 


N02 


HYDES 


HCN 


H2S 


CI2 


HOI 


GENE 


6/13 


1 











0.04 














6/14 


2 











0.35 














6/15 


3 








- 


0.32 

















6/16 


4 











0.27 












6/17 


5 











0.25 












6/18 


6 











0.27 

















6/19 


7 











0.33 












6/20 


8 











0.27 












6/21 


9 











0.27 












6/22 


10 











0.28 

















6/23 


11 











0.25 












6/24 


12 











0.31 












6/25 


13 











0.29 

















6/26 


14 











0.35 












6/27 


15 











0.27 












6/28 


16 











0.30 












6/29 


17 











0.27 

















6/30 


18 











0.26 












7fl 


19 











0.27 












7/2 


20 











0.47 

















7/3 


21 











0.33 












7/4 


22 











0.38 












7/5 


23 











0.24 












7/6 


24 











0.38 

















7/7 


25 











0.31 












7/8 


26 











0.33 












7/9 


27 











0.34 

















7/10 


28 











0.32 












7/11 


29 











0.34 












7/12 


30 











0.32 












7^3 


31 











0.33 

















7/14 


32 











0.33 












7fl5 


33 











0.34 












7/16 


34 











0.33 











D 





7/17 


35 











0.34 












7/18 


36 











0.34 












7fl9 


37 











0.31 












7/20 


38 











0.35 

















7/21 


39 











0.31 












7/22 


40 











0.28 












7/23 


41 











0.29 

















7/24 


42 











0.34 












7/25 


43 











0.23 












7/26 


44 











0.23 












7/27 


45 











O.ZI 


















152 



TABLE 3 - Concluded 





TEST 








ALDE- 


DATE 


DAY 


NH3 


SO2 


N02 


HYDES 


7/28 


46 











0.31 


7/29 


47 











0.30 


7/30 


48 











0.28 


701 


49 











0.32 


8ft 


50 











0.25 


8/2 


51 











0.29 


8/3 


52 


0.5 





tr 


0.31 


8/4 


53 


0.5 





tr 


0.34 


8/5 


54 


0.5 





tr 


0.34 


8/6 


55 


0.5 





tr 


0.34 


8/7 


56 


0.5 





tr 


0.35 


8/8 


57 


0.5 





tr 


0.33 


8/9 


58 


2.8 





tr 


0.33 


8ft0 


59 


1.9 





0.1 


0.32 


8ftl 


60 


2.8 





0.1 


0.30 


8/12 


61 


0.5 





tr 


0.33 


8ft3 


62 











0.32 


8ft4 


63 











0.33 


8a5 


64 











0.25 


8/16 


65 











0.26 


8ft7 


66 


tr 








0.30 


8/18 


67 


1.4 








0.31 


8/19 


68 


1.9 








0.25 


8/20 


69 


2.4 








0.33 


8/21 


70 


1.4 








0.31 


8/22 


71 


1.3 








0.33 


8/23 


72 


tr 








0.34 


8/24 


73 


tr 








0.35 


8/25 


74 











0.37 


8/26 


75 


tr 


- 


- 


0.38 


8/27 


76 


1.3 








0.39 


8/28 


77 


1.6 








0.39 


8/29 


78 


1.8 








0.30 


8/30 


79 


1.3 








0.27 


8/31 


80 


1.6 








0.23 


9/1 


81 


1.8 








0.32 


9/2 


82 


1.8 








0.31 


9/3 


83 


1.8 








0.38 


9/4 


84 


1.1 








0.39 


9/5 


85 


1.8 








0.39 


9/6 


86 


1.8 








0.39 


9/7 


87 


3.5 





0.15 


0.42 


9/8 


88 


4.0 





0.12 


0.41 


9/9 


89 


1.8 





tr 


D.43 


9ft0 


90 


0.5 





tr 


- 



HCN 



H2S 



HCl 



PHOS- 
GENE 



ALLVALUES IN PARTS 
PER MILLION 



8/8 STOPPED FEEDING WICK 
8/9 AFTER STARTING TO DRY WICK, 
AAORE NH3 FORMED FROM Wl CK 
DEPOSITS AND WAS RELEASED 
INTO CABIN AIR 

SaiCORREUTIONBmVEEN 
NH3 AND (NO)x 



8/19 TOXIN BURNER TURNED OFF 



8/19 



8/21 



WICK EVAPORATOR PRE- 
HEATER LEFT ON SINCE 
PREVIOUS USE OF WICK 
EVAPORATOR WAS TURNED 
OFF WST NIGHT 
FLOOR WAS WASHED WITH 
COo CONDENSATE WATER 
FROM SOLID AMINE 



9ft 

9ft 
9ft 

9ft 
9/2 



SOLID AMINE SYSTEM 

DISCONTINUED 

MOLECULAR SIEVE STARTED 

WICK EVAPORATOR 

STARTED 

VD-VF DISCONTINUED 

TOXIN BURNER BURNED ON 



HaE IN SABATIER EXHAUST LINE 



153 






< 



LU 
N 
UJ 

^ u- 

o 

Z 



O 
o 



3N31AX-M 


1 1 i 


MUOdOUOlHO 


1 1 1 


)i3VU 


• 1 • 


3aiU01H3ia 
3N31AH13 


t 1 1 


3NVX3H 
-OlDAO 


i 1 1 


10NVX3H 
1AH13-Z 


• 1 • 


lONvina 

nAH13-Z 


• • • 


lOHOOlV 
lAHi3 


1 • • 


3N0133V 


• • • 


3Namoi 


• 1 • 


dl N03Ud 


• • • 




UNMANNED 5-DAY 

4-28-70 
SECOND DAY OF 54)AY MANNED 

5-1-70 
FIFTH DAY OF 54}AY MANNED 

5^70 



lOHOOlVlAWVOSI 


1 1 • 


3aAH3aiVU31VA-N 


• 1 1 


lOHOaiVIAWVN 


• 1 1 


3N013)I 

lAineosnAHiara 


• 1 1 


3N31AXO 


• i 1 


3N31AX-d 


• 1 • 


10H001V 
lAdOUdOSI 


• • • 


3NVld3H 


1 • 1 


3NVH13N 
0U01H3ia 


1 • 1 


10H001V 
1AHX3M 


• • 1 


lOHODlV 

lAina 


• 1 1 


3NVin8 
lAHlSMia 'tz 


• • • 




UNMANNED 543AY 

4-28-70 
SECOND DAY OF 5-DAY MANNED 

5-1-70 
FIFTH DAY OF 5-DAY MANNED 

5-4-70 



M 

K 
Ul 



s 

lii 

S 

3 
-I 

a. 
S 



3 
O 



O 

z 



UJ 
CO 

UJ 

E 



UJ 



15^^ 



TABLE 5 
CONSTITUENTS OF WEEKLY FREEZE-OUT SAMPLES 



DATE 


TEST 
DAY 


LU 
Of 


Ixl 

s 

=3 


LU 

o 

< 


ETHYL 
ALCOHOL 


2-ETHYL 
BUTANOL 




CYCLO- 
HEXANE 


ETHYLENE 
Dl CHLORIDE 


a 

S 


o 

X 

o 


LU 
1 


6-15-70 

6-23 

6-30 

7-7 

7-14 

7-21 

7-28 

8-5 

8-11 

8-18 

8-25 

9-1 

9-8 


3 
11 
18 
25 
32 
39 
46 
54 
60 
67 
74 
81 
88 






• 


• 
• 
• 
• 
• 
• 
• 
• 

• 
• 
• 




• 

• 
• 
• 

• 

• 

• 


• 




• 


- 


• 
• 
• 
• 

• 
• 
• 



NOTE: • PRESENT 



NOT FOUND SAMPLE VOLUME: 60 LITERS 



TABLE 6 
CONSTITUENTS OF WEEKLY FREEZE-OUT SAMPLES 























t 


5^ 


LU 
O 

>- 


X 






1 


_J 


_i 


o 

^ LU 


1 1 1 


- _j 

>- 


LU 


LU 


QQ 
O 
I/) 


o 

1 

< 


X 
LU 

3 

< 


o 
o 

< 

1 


DATE 


TIST 


1^ 


O 
_, X 


_J o 
>- X 


2i 


•z. 


o o 


LU 

1 


IZ. 

LU 

1 


^g 


>- 


UC- 


>- 




DAY 


CM^ 


^§ 


X o 
!p — ■ 


11 


LU 


o o 


>- 

X 


> 




< 

1 


% 








CM OO 


CO < 


S < 


cs S 


X 


_ < 


Ql. 


o 


S ^ 


z. 


z. 




6-15-70 


3 




- 


- 


• 


- 


- 


- 


- 


- 


- 


- 


- 


6-23 


11 




- 


- 


• 


- 




- 


- 


- 


- 




- 


6-30 


18 




- 


- 


- 


- 




- 


- 


- 


- 


- 


- 


7-7 


25 




• 


- 


• 


• 




• 


- 


-' 


- 


- 


- 


7-14 


32 




- 


• 


• 


• 




• 


- 


■■- 


- 


- 


- 


7-a 


39 




• 


- 


• 


• 




' • 


- 


- 


- 


- 


- 


7-28 


46 




• 


- 


• 


- 




• 


- 


- 


- 


- 


- 


8-5 


54 




- 


• 


- 


• 


- 


- 


- 


- 


- 


- 


- 


8-11 


60 




' • 


- 


- 


• 


- 


- 


- 


- 


- 


- 


- 


8-18 


67 




• 


• 


• 


• 


- 


• 


- 


- 


- 


- 


- 


8-25 


74 




• 


- 


• 


- . 


• 


• 


- 


- 


- 


- 


- 


9-1 


81 




• 


- 


• 


• 


• 


• 


- 


- 


- 


- 


- 


9-8 


88 




• 


• 


• 


- 


• 


- 


- 


- 


- 




- 




NOTE 


• 


PRESENl 


- 


NOTFOL 


IND 


SAIV 


iPLEV 


OLUM 


E: 60 Lr 


fERS 







155 



FREON TF AND ACETONE CONCENTRATION 



z 
p 



1.0 
0.8 
0.6 



B 0.4 

< 
0.2 





10 



\Si 



l-X 1.H ,2.34 
■ ' ' 11 


1 L I !• 


ffiki iU\- iiiat^C 


_, lAa^^O^V^i^I^" 


2 -^p Wr -t-^t 


rv^ 




:: r 


« , 1 


iL^^T.^a^a^ 


VA^lV^^N^t^ 4r»^^^-4^p 





6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 
TEST DAY 



Figure 1 



ATMOSPHERIC TRACE CONTAMINANTS IN 90DAY TEST 



1 '^'^ 

o. 



0.10 
0.05 



f0.70 

A 

u / \ 

/ \ 

I \ 



i 



ETHYL ALCOHOL 




12 



24 



TOLUENE 




36 48 60 

TEST DAY 

Figure 2 




72 



84 



% 



156 



ATMOSPHERIC TRACE CONTAMINANTS IN &0-DAY TEST 



_ 0.3 

s 

Q. 

a. 

^ 0.2 

< 

2 0.1 

X 

o 
a 


0.3 

I 0.2 
a. 

UJ 

S 0.1 



OICHLOROETHANE 




JllUi 



METHYLETHYL KETONE 



12 24 



36 48 

TEST DAY 

Figure 3 




60 72 84 96 



ATMOSPHERIC TRACE CONTAMINANTS IN 90-DAY TEST 




S 0.6 

Q- 


2 - ETHYL BUTANOL 


1 0.4 

CO 


^^r^/^A/^ n nuA/ifiA/ a/ 


g 0.2 

UJ 


-M vWuuWa] u u J 


■^ n 


1 1 1 1 1 1 1 



12 



24 36 48 60 72 84 96 

TEST DAY 



Figure 4 



157 



METHANE AND CARBON MONOXIDE CONCENTRATION 



30 



20 



10 























r~ 






/ 


• "" 


--- 





A 
























,-~ 


~^ 


< 1 1 

/ ^METHANE 












■' 


"v 


^ 


»»— 


h- 


— ^ 




















/ 




\ 






















/^ 


A^V 






/ 




\ 












1 




A 1 




J 








\/^- 


I 






\ 


V 


\. 




/V 


'\ 


J 


^CARBON MONOXIDE 


JERC 






1 


lUi. 








X 






^ 








1 ^ 

TOXIN BUR 


■ 
FF 





300 



200: 



100 



10 20 30 40 50 60 70 80 

TEST DAY 



90 



Figure 5 



158 



MEASUEEMEaST OF TRACE AOMOSPHERIC CONSTITUENTS 

m THE 90-MY SPACH STATCOW SIMULATOR 

?y M. L. Mdberg and C. L. Deuel 

Analytical Research Laboratories 
Aerojet Electrogystems Corapaiay 

ABSTRACT 



The significant analytical data and methods of collecting trace atmospheric 
cqatponents found during the 90-day manned space chamber test are reviewed. The 
three collection methods and special sampler used on this program provided sam- 
ples for measuring the major, minor, and trace components with classical gas 
volumetric analytical precision throughout the dynamic range and with reasonahle 
turnaround time. Approximately 100 components were identified and quantitatively 
measured using gas chromatography, mass spectrcanetiy, infrared spectrophotometry, 
and high-vacutm rack manipulation. With relatively few exceptions (and somd 
minor test difficulties) the SSS atmosphere was found td he of higher quality 
than the average troposphere. It is "believed that these data will also serve 
as a base for parametric auto- instrumentation. 

HiTROroCTION 



The purpose of this program wa? to measure the trace atmospheric constit- 
uents found in the Space Station Simulator and expediently report these data to 
the technical monitor for medical siirveiUance. This information was also used 
to verify automatic instrumental monitoring of selected coiiirponents. i)uring this 
study more than 100 conrpoimds were identified and quantitatively measured using 
state-of-the-art gas chromatographic and mass spectrometric techniques. 

SAMPnCNG 



Three methods of sample collection were employed using the general proce- 
dure shown in Figure 1. The credence of all chemical analytical data depends 
on the reliability of sampling. For this reason principally, and in addition 
to the inherent weaknesses in any single known sampling method, three accepted 
procedures were used. These were charcoal adsorption, ciyogenic sample collec- 
tion, and direct or "grab" sampling. As shown, the activated charcoal system 
was arranged for parallel or serial collection with the direct and cryogenic 
system. For this program a sample of the chamber atmosphere was continually 
directed through one of the collection modes. A pictorial view of the complete 
sampler is shown in Figure 2. This sampler, though modified to accept the 
charcoal system, was iised earlier for the Apoila "J, 8, and LEM atmospheric 

159 




studies. It is the property of the Langley Research Center (fabricated lay the 
Atlantic Research Corporation). Figure 2("b), a side view of the saitrpler, shows 
three charcoal adsoorption tubes serially arranged to remoye trace constituents 
from the chamber gas stream. 

Each adsoarption tube contained approximately 100 g of Bamehey-Chepey AC 
charcoal. Before use the charcoal was thermal- vacuum treated and periodically 
examined as an analytical sajiple to assure the program that no contaminant 
would he added to the chamber and that each sample would represent only the 
components collected from the chamher. Ihe cryogenic system consists of four 
stainless steel collection cylinders each having a capacity of 500 ml. The 
first trap was operated slightly helow 0° C, the 2nd at -8o° C, and the third 
and fourth at the boiling point of liquid nitrogen (approximately -190° C). 
Grah samples were taken with cylinders similar to the ones used for cryogenic 
collection. 

Gas flow for this collection system is shown in Figure 5. Two Diapuntps, 
manufactured hy Air Ccaiti*ols, Inc.^ were used to moye and return the chamber 
atmosphere through the collection system. This system offered independent flow 
control from, the Gas Analysis Console pun5)S, a desired redundancy. Gas flow 
rates for the ciyogenic system, corrected to 7^0 torr pressure, were varied 
dowQ-ward from approximately 1000 to 750 cc/min in an attempt to improve collec- 
tion efficiency. Differences in amount collected between the adsorption and 
cryogenic systems are discussed later, ¥ith the sanrple collection ^stem and 
flow chart shown, a continuous surveillance of the chamber atmosphere was main- 
tained. The schedule for each collection method was varied somewhat to accom- 
modate special analytical requests of the technical monitor. This variation 
was minimal however and Figure k- shows the schedule used for the middle month 
of the program. A total of 25 grab samples, 28 cryogenic sample sets, and 
28 charcoal collections were taken during the course of the test. Periodic 
checks on gas flow (measured with Matheson Mass Flow Meters) were made by 
McDonnell Douglas personnel when the Aerojet team was off site. 

AmLYTlOAL METHODOLOGY 



The samples were raaoved from the sanrpler, brought ta the Laboratories, 
analytically divided into 5 fractions and analyzed generally within a 2k hour 
period. Occasionally, special analyses were made in the same 8 hour period of 
sampling when some question of atmospheric contamination was suspected. Each 
sample was handled on the laboratory high-yacuum system shown in Figure 5« 
This equipment, which included the metal system on the other side of the rack, 
was maintained at pressures below 10^5 toan: when not employed for sample manip- 
iilation. Periodic blank samples were analyzed to assure the analyst that the 
data generated frcm the test san^jle was not biased from equipment contamination. 
Cleanliness of the sample cylinders was also verified by this periodic spot 
testing. 

Each charcoal trap was transferred in an inert atmosphere box to a 200 ml 
round bottcaa flask and attached to the vacuum system as shown in Figure 6. The 

l60 



flask was temperature programed from am"bient to 170*^ C at a rate approximating 
10^ C/min. The effluent was directed through -80° C U- traps and two special 
Schultz traps shown in the upper right side of Figure 5. After 1 hour of 
desorption, the products were transferred to receiving flasks fox analysis. 
The total system is fitted with Fischer-Porter teflon high- vacuum stopcocks. 

The direct atmosphere and ciyogenically collected samples were split into 
equal fractions, by alternately using vacuum and helium pressurization, using 
the system schematically shown in Figure 7. Each was imiformly expanded inta 
5 evacuated receivers, the saniple cylinder purged with helium (if required) and 
this product added to the receiver manifold. All connecting systems, sample 
cylinders and receivers were maintained at 80° C. After each sample split, the 
system was vacuum thermally cycled 5 times to insure cleanliness for the fol- 
lowing runs. 

The major analytical tool supporting this stu^ w«.s the instrmaent complex 
gas chromatography-mass spectrometry. Figtare 8 shows the F&M Model 5'}^6 Chroma- 
tograph fitted with flame ionization, electron c'scpttire, and theamal conductivity 
detectors each separately recorded, and an Infotronics HSll integrator coupled 
to the FID mode. The sample inlet system, constnicted hy the la'boratories , is 
fitted with packless "bellows valves. The arrangement is such that with the 
sample fraction attached, the connecting tube, sample loop and a portion of the 
inlet system can he evacuated and helium purged while under a controlled tem- 
perature of 100° C. Figure 9 illustrated the sample flow. The instrument is 
fitted with a Porapak Q and a Carhowax 1000 column. These are operated alter- 
imtely, one analyzing and the second hackf lushing. !El.ow direction is controlled 
with Circle Seal Valves located within the column oven. The column effluent is 
directed to the detectors in the approximate percentages shown: 65 to FID, 
2 to ECD, 25 to TCD and 10 to the mass spectrometer. 

The Consolidated 21-lOij- mass spectrometer (l^), shown in Figure 10, is 
attached to the chromatograph with a short heated line. This line is directed 
to the analyzer input where a portion of the sample enters and the remainder is 
removed through a second vacuum system. While the laboratory has identified 
this inlet system as "a direct in-line inlet" the introduction to the ajialyzer 
resembles a I^hage ventiiri. Spacing of the column effluent line to the analyzer 
inlet opening is somewhat ciltical and optimum i^sponse is achieved through 
experimental positioning. Other capabilities of the MS vised on this program 
include a total ion monitor and special sweep selectors for monitoring selected 
m/e ranges. The latter was used for following three particular coniponents, 
ammonia I7, foimaldehyde 50, and sulfur dioxide 6k amu. Finally, a number of 
special measurements were made using infrared spectrophotometry and a long-path 
gas ceU. The data obtained from these measurements were in agreement with 
separate MS measurements. 

MALYTICAL DATA 

The analytical data acquired on this program are too massive to be conven- 
iently reported here. However, I will tiy to present significant observations 
on selected data, cong)are the collection systems on the basis of material 

161 



recovery, and show a typical chromatogram. Very significant increases in 
chamber atmospliere contamination during the 90-diaj period were not ohserved. 
Prestana'bly the "clean air" condition was directly related to the chamber air 
pitrlflcatlon system.. On one occasion the Laboratory had the opportunity of 
examining several charcoal saarples from the Wick Evaporator. These data were 
interesting in that ha;logenated materials (e.g., freons, halogenated unsaturated 
hydrocarbons, methyl chloroform types) and low-boiling hydrocarbons showed 
extensive penetration "while the higher boiling hydrocarbons and oxygenated 
materials generally were collected on the first layers of charcoal. Por example, 
Preon 115 shewed a bed penetration in terms of ng/g charcoal of lOyo at the 
inlet, 1690 at the center, and 528O at the exit of the purifier. Analyses of 
the new charcoal was 3-0 Us/s» Methyl acetylene and methyl chloroform increased 
10 fold and trifluorochloroethylene 50 fold. Conversely, acetone and methyl 
alcohol decreased by a factor of 5« These data might suggest a reason for the 
atmospheric compositional variations occurring during the 90-day study. Total 
product recovery -was examined from the three collection methods. These data 
indicate that direct sample collection appears to provide the greatest calcu- 
lated contaminant concentrations although signal responses were quite low in 
most cases. Cryogenic sampling provided a concentration factor from 50 to 
100 times, while the q.uantity of gas san^led with charcoal was frcan ^0 to 
2000 times that of the grab sample. Considering the dynamic range of conrpound 
concentrations and quantity of gas sampled (10°) the observed disparities might 
not be considered too serious. A comparison of the cryogenic and adsoiption 
data are shown in Figure 11. Let us examine these data for a moment. Excluding 
water, carbon dioxide, Fx^on II5, and the major atmospheric components, the 
values shown represent the remaining total collected material. Flow rates 
through the charcoal started at 1 lj.ter/mln were reduced to 750 cc/min, to 
500 cc/mln, and finally to a rate near 100 cc/min in an attentpt to attain recov- 
eries approaching those of the cryogenic system. Likewise, cryogenic collection 
was made for the first 5 sets at 1 liter/mln, decreased to 750 cc/min and finally 
(the last 2 sets) to appro xim ately 5OO cc/min. It is suggested that differences 
in the data obtained from these methods were, in part, due to elutlon of the 
adsorbents (with HUO and CC^] or deactivation of the charcoal. On addition of 

a drying agent and later lithiimi hydroxide plus Drierlte after day 56 as a 
pretreatment column for the adsorption system, a marked Improvement in reeovezy 
was observed. Either proposed mechanism coxxld substantially reduce the ettttount 
of minor constituents adsorbed by a given amount of charcoal. A portion of 
thi^ study is continuing under HASA Contiuct HAS 9-110i|-9, 

The change in observed concentration of severeil constituents was followed 
throughout the ^-day test. These data are showi In Figure 12. While this 
figure is a little too "busy," some observations can be abstracted fjpom it. 
ilrst, Freon 115 quantities are shown for all three collection systems. Dif- 
ferences between direct and cryogenic sampling generally remain the same 
throtighout, e.g., a factor of 2., except for a few perturbations. The charcoal 
recovery was improved by pred3^1ng the gas stream although recoveries were 
never equivalent. Recall for a moment the information obtained on the Wick 
evaporator charcoalj the halogenated hydrocarbons were poorly retained or easily 
desorbed. Trijfluoaxjchloroethylene (TFCE), shown on the charcoal graph, is an 
impurity in the Freon II5 solvents or a degradation product of one of the freons. 
Its concentration varies rather consistently with Freon II3 at about 10^ of the 

162 



latter. Benzene, a material -with a relatively high adsorption isotheim> showed 
a generally increasing trend throtjghout the test. Even with benzene a meastir- 
able increase was observed after water was removed from the atmospheric gas 
stream. 

Acetaldehyde and isqprene, two Isnown human exudates, were followed through 
the test. A general concentration buildiap wus expected hut did not materialize. 
This may i>e related to their relative chemical instabilities. Finally, ethyl- 
benzene and isopropyl alcohol (IPA) were followed on the direct sample data 
sheets. With the exception of 2 or 5 samplings, a generally increasing level 
for IPA would indicate a decreasing capacity of the purification system. If 
the large charcoal scrubber reached a saturation level for organics, however, 
large changes woxxld have been observed for all organics. Ethylbenzene varied 
rather randomly during the test. 

Figure 15 illustrates the generally increasing trend of contaminant buildup. 
Hote that one CfS the sample containers used for the 57 day cryogenic collection 
had faulty valveS. This failure was not bbseived until after the sample set 
was taken. Freon 115 ^ta was omitted from this figure because rather enormous 
concentration variations were observed and the general trend in all other pi-od- 
ucts would have been obscured. Figure ih shows the chromatograms of 2 selected 
samples. As mentioned earlier, two chromatographic colxanns vere used for every 
sample. A 12-ft by l/8-in. Porapak Q column was temperature programed from 
500 to 150° C at a rate of h degrees/min. Most of the low boiling hydrocarbons 
and halogenated materials were resolved on this column. After approximately 
60 minutes of operation this column was backf lushed and a second split sanrple 
introduced into a 20-ft by l/8-in. Carbowax 1000 (10^ on Gas Chrom Q) column. 
This column was programed from 50° to 150° C at a rate of h degrees/min and run 
for approximately ^5 minutes. Ai*n3WS from one chramatogram to another illus- 
trate the conrplimentary natxire of both columns and the increased analytical 
capability that is achieved with duo-colimm operation. Each of these columns 
were operated with a matched coliimn used for equalizing flow rate and providing 
a stable baseline. 

A number of other experiments were conducted for the program. These 
included measuring total water recovery for the project, following the level 
of methane, carbon monoxide and hydrogen with IE and MS, analyzing several 
breath sa3i5)les taken in teflon cylinders and analyzing coolanol for its impur- 
ities, stability, and deccaaposition products under thermal and oxidative 
degradation simulating chamber spiH conditions. 



165 



ct 

It o 



lO 




a: 
OS 

(T-J 
U. 3 

1-1 

^^ 
(0 



^ 



a 

■+-> 
09 
>. 
CO 

faD 





U) 


a 




UJ 


rrt 




o 


CQ 


JL Q 




Q?) E 


ca 


J 


1- 
a: 


O 




<t 


1 




o 


• 




-J 




JL < 


O 


(x> O 


!h 


pi-, or 


§} 




< 

X 


fe 




o 





<8>-()-<8>- 



l6k 








(a) Front view. 

Figure 2.- NASA sample acquisition system. 



(b) Side view. 



165 




166 



?^ 



< 
o 
o 

< 

31 



CM 



< 

o 
o 

< 

o 



CM 



o 

o >- 

CM ^ 
O 



O _| 

o^ as O 
'- o^ < J^ 



NO 



O 

< 
o 



oo 

CM 



o 

CM DC 
O 



VO < 

CM q: 

«^ -I 

< 
o 
o 

cc 

< 

X 

o 
m 

CM 






!5 



o 

< 
m 



S 



o 

>- 
oc 
o 



o 

CM ca 
O 



CD 

««^ <C 

^ -I 

< 
o 
o 

cc 
< 

3= 

o 

CM 
CO 



o 
o 



CM 



o 
o 



QQ 

o < 

^ CC 
O 



o 

< 
X 

o 



cr> 



< 

o 

X 

o 



o 

O 



CD 



< 


< 


o 


o 


cr> O 


o o 


CM q; 


rr» QC 


< 


< 


X 


X 


o 


o 



o 

oo >- 
crv OS 

O 



< 
O 

ro DC 

< 
X 

o 



:§ 



o 

uy >- 

o 



o 

< 

X 

o 



a 
o 

xJ 
u 

0) 
I— I 

I— I 

o 
o 

<u 

1-4 

I 

09 



I 

< -a 
o o 
o «J 

X U 

o -S 



S 






^ 



167 



, "J 



=^siis^v.-->*t?';;?r:a& 






V 



»»»- 



1>» ; 



>S,v- 






'^ 



, I 




^^^ ^^ -^Tl gi'ife«^.iv.;*:> •::; f ■■■■ 







- -t ■ 









r 

> * 







*•' i 






! 









■J* 



vs .. 









v^ ...... ,. 









fc...' 



o 

■rH 

CI 

a 

(a 
ni 

GJ 
o 



111 

O 
U 



3 
o 

> 



in 



pt, 



168 










^ -*^ '^l*p**v 



"(f^rv^lISi^ F %«^ 










T« »«' 



^s^'-r^^rv 



■<iF ^Efaw. 






- .^ ** 



^ < "^-Rr. i>f« ;-» \ ife- 

«|g^ ■T''^^. ^"t^ *'t,-|'** 

H ^ .kX.«.^ ^.imA.. .^.c^ aJf^^lJS "* AJMblbeV 













9: 



\: 



V .«;. 





•- 1r * 




169 



UJ 




03 



a 
<a 

■M 
O 

<0 
ft 
I— I 

o 



u 

•iH 

a 

bO 

o 
o 

•1-1 

•r-l 
I— I 

OQ 
1— I 

t 

CQ 
I 

• 

t- 

<a 
u 

?J 
bfi 

•1-4 

;i>4 



170 




r-nm 



\; .**. 













;j> 






M'; 









171 



00 



X 
CO 

3 


CM •> 


u. 


^5 


o 


ujq: 


<r 


Wo 


m 

1 






S 

a 
a 
S 

o 



o 

s 

o 

M 

o 
O 






172 



;;'>•■■- 







4 '' ' 



^^^ i 









IT'^-r 



'i 



I 









-s*. 







■"■**,. 



ft 













$1 

-M 

a 

o 

-M 

o 


ft 
m 

09 
CQ 






fa 



l#«>4>j|>4«tf»' 



.... ^, 




175 








< z 

O ui 

u o 

Be o 

< >■ 
X Of 
u u 



(eii Noand ssai) (Kvovti 'N0iivaiN33N03 iNaiiVddv 



ijk 




o 

S 

o 
a 

•o 
o 

■M 
O 

o 

<rt 1—1 



I 



o 
a 

■s 

o 

o 
U 



CSI 

o 



lOHODlV lAdOadOSI 

■J 3NazM3a-iAHia 

I I I l_ 

eii Noaad 



3N32ldOSI 

■8 aaZaarfliof 



3N3ZN3a 

I I I I I I 



11 L 



I 



J II L 



33dl 

J l_ 



J I 



o u) in 

•o • =? 

eil N03ild 
gW/OW N0liVaiN33N0D 



CIL NOaiid 



175 




CO 



o 
o 
u 

1=1 

r— 1 
O 



f-i .1-1 

•" +3 t) 

^ »- g S 
o T3 
U 



o 
o 

0) 



o 
o 

u 

•l-l 

a 
o 
bJO 
o 
>. 

O 
hfi CQ 

r— I 

-M 
O 

H 
I 

CO 

1-1 

o 
u 
7i 



gl/t'OW 



176 







■s 

o 
u 

0) 

y 

ai 
U 

-M 

o 

a 

u 
O 

S 
o 

O 

0) 

O 
CD 

1—4 






17I> 



RESULTS OF THE AEROSOL ANALYSIS EXPERIMENT PERFORMED 

DURING A 90-DAY MANNED TEST OF AN ADVANCED 

REGENERATIVE LIFE SUPPORT SYSTEM 

By Walter F. Harriott and Robert A. Walter 
DOT Transportation Systems Center 

SUMMARY 

Preliminary results from the aerosol analysis ejcperiment are presented. 
The membrane filter data indicate the trend of particulate concentration in 
the simulator. The filters have also been partially analyzed by scanning 
electron microscopy for particle type. Close correlation in particle pro- 
duction has been found between submicrometer and micrometer particles and the 
particle producing activities within the simulator. 

INTRODUCTION 
The objectives of the aerosol analysis experiment were three-fold: 

(1) The primary purpose was to measure particulate concentrations and 

size in the simulator during the 90-day test of a regenerative life support 
system and to evaluate particulate removal hy the environmental control 
system (ECS) and the generation of particulate matter by housekeeping practices, 
experiments, and equipment. 

(2) Provide baseline data in support of Skylab Experiment T-003, In- 
Flight Aerosol Analysis, which is to be flown to assess the spacecraft parti- 
culates generated in the Orbiting Workshop. 

(3) Evaluate the condensation nuclei counting technique as a means of 
detecting suhmicron particles from overheated materials and their applicability 
as a warning of prefire conditions in spacecraft. The simulator provided an 
environment similar to a spacecraft, which could be used for determining the 
interfering activities that would give rise to false alarm signals and for 
establishing a baseline background count. 

To achieve all the goals of the experiment, analysis of data is being made 

to determine the levels of particles and their variation with time within the 

179 



closed simulator envlronmentj to determine tlie gross physical and chemical 
characteristics of the aerosols; to determine the extent of correlation among 
measurements taken by different techniques at different locations j to 
determine the extent of correlation of particle concentrations, variations, 
and characteristics with operating conditions and activities in the simulator; 
to evaluate activities and operating conditions as to their production of 
particulate matterj and to provide baseline information for modification and 
improvement of current sampling techniques. 



PROCEDURE 

Three measurement techniques for particulates were employed for the 
experiment . 



Filter Air Samplers 

Membrane filters with a pore size of 0.8 ym and preloaded into plastic 
holders were used at locations 1 through 4 (fig. 1). An airflow of 5 liters/ 
minute was maintained by a pump inside the simulator. The filters at locations 
1 and 2, food preparation and waste management, were changed daily; locations 
3 and 4, air return and air supply, were changed weekly. 



Light Scattering Equipment 

Four inlet lines terminating adjacent to the membrane filters were 
sampled sequentially at approximately one hour intervals throughout the 90 days, 
with the particulates being drawn In at 17 1/mln airflow through a light scat- 
tering particle monitor (Royco Model 245) located outside the simulator chamber. 
The count and sizing information for particles from 0.5 to 10 ym was obtained 
by sorting the pulsed output of the light scattering Instrument Into 512 chan- 
nels of a multi-channel pulse height analyzer (Nuclear Data Model 3300) and the 
results stored on computer compatible magnetic tape (Datamec Model 2020) . In 
addition, the analog output of the light scattering Instrument was recorded on 
a strip chart recorder (Royco Model 503) for the Integrated particle count of 
0.5 to 10 micrometers. 



Condensation Nuclei Counter 

A condensation nuclei counter (General Electric Model PCNC-1) was located 
at station 3, the air return. This Instrument gives a gross count of particles 
from 0.001 to 0.1 ym by light extinction measurement. The Instrument was modi- 
fied for use at 10 psl and 110 V AC power and had a large water reservoir added 
for reduced maintalnence. The condensation nuclei counter operated continuous- 
ly for the whole test, with the counts recorded on an external analog strip 
chart recorder. 

180 



RESULTS 

The particles collected on the membrane filters were counted and sized by 
optical microscopy in three ranges: less than 2 pm, 2 - 5 ym and greater than 
5 um. Fig. 2 shows the results in the three size ranges for the food prepara- 
tion area, station 1. 

Peaks and trends observed in the food preparation area, station 1, were 
found in the waste management areas. Weekly trends reflected in the air supply 
and return filter samples correspond to the weekly averages of the food prepa- 
ration and waste management areas. 

All three size ranges show similar peaks and after an initial cleanup of 
the simulator a buildup of particles continues through day 50. From day 50 on 
the trend is downward for the particle counts which can be attributed to more 
routine operations by the crew, and buildup of a filter cake on the ECS fil- 
ters resulting in more efficient filtering. 

The high counts around day 28 are the result of radioactive source change 
and maintenance on the vacuum distillation - vapor filtration unit. Micro- 
scopic examination indicates that the particulates consist mostly of clothing 
particulates from the high workload to accomplish the changeover with some 
contribution from filter material removed from the unit. Other peaks are from 
days of increased general activity by the crew. 

The filters were also examined by scanning electron microscopy for evalua- 
tion of particle morphology. Typical results are shown in fig. 3 with tenta- 
tive identifications of the observed materials. 

Figure 4 shows a 12 hour readout of the light scattering instrument and 
condensation nuclei counter. The agreement between the two curves is quite 
good and this was typical over the full 90 days of the test. 

Both the condensation nuclei counter and the light scattering instru- 
ment peaks were correlatable throughout the simulator test period to waste 
management, food preparation and eating, various exercises, body hygiene and 
laundry and biomedical checking devices such as the Langley psychomotor test 
and himan describing function. 

In active periods, the light scattering instrument recorded up to 30 
peaks in an eight hour period; and superimposed on activity peaks, simulator 
cyclic events were noted at eight different intervals during the 90 days. 
These events had frequencies of 1 per 15 min, 1 per 26 min, and 1 per 45 min 
with characteristic peak shapes. Fig. 5 shows a day when the 45 min peak 
dominated in particle production. 

A check of engineering data shows that there is an automatic cycling of 
filter beds in the molecular sieve on the CO2 concentrator every 45 
minutes . 



181 



A condensation nuclei counter could be used as an incipient fire detector 
in spacecraft if the normal activities did not give rise to an excessive false 
alarm rate and this test served to establish the condensation nuclei production 
from common activities. With an anticipated 10,000 particle/cm3 prefire detec- 
tion threshold level in a spacecraft of Skylab size, the 90'=^ay test indicated 
satisfactory performance. On very few occasions, vacuum distillation - vapor 
filtration maintenance and alpha filter changes, the level rose to higher .than 
10,000, whereas a frozen pump motor indicated clearly an overheated condition. 



FUTURE STUDIES 

Work is continuing on examining the filters by scanning electron micro- 
scopy. In addition, an electron probe will be used for elemental analysis of 
the particulates of interest. Particles from samples of the common materials 
in use in the simulator such as clothing, bedding, curtains and soap are being 
compared to those observed on the filters. The filters from the environmental 
control system have been obtained from McDonnell Douglas and the filter cake is 
being examined chemically to determine its composition. 

The tape readouts from the light scattering unit contain the particle size 
diatributions and these are being analyzed for comparison of distributions to 
the producing activity. 



ACKNOWLEDGEMENTS 

This experiment was supported by the Biotechnology and Human Research 
Division of OART, Walton Jones, M. D., Director, and the NASA Spacecraft Fire 
Hazards Steering Committee, I. Irving Pinkel, Chairman. 

Drs. Parker Reist and Christopher Martin of the Harvard School of Public 
Health substantially contributed to the experiment definition and preparation 
of the filter experiment. 



182 



§1? 



< S o 




<» 

o 

o 



0) 



• iH 

0) 

13 



o 

CO 

o 
u 
o 

< 



<x> 
u 



185 



3000 




-I 
o 



(a) Particle size < 2 juim. 




(b) Particle size from 2 to 5 jLim. 




(c) Particle size > 5 /xm. 
Figure 2.- Filter results for food preparation area, 

station 1. 



1814. 



• -•^: 



*;fe. 






# * 



(A) 



UNKNOWN 




UNKNOWN 



SKIN 
FLAKE 



FIBER 



CRYSTALLINE 
MATERIAL 




UNKNOWN 

-A m 




(C) (D) 

Figure 3.- Scanning electron photomicrographs of filters for day 28. 



185 



4K 



DAY 75 
0000-1200 HRS 




0100 



0200 0300 0400 



0500 



0600 0700 0800 0900 1000 
TIME 



1100 



1200 



(a) Condensation nuclei counter (0.001 jum to 0.1 jum). 




a FILTER CHAN6E 
a LUNCH 



LRCa * 





0100 0200 0300 0400 0500 0600 0700 0800 0900 1000 1100 1200 

TIME 

(b) Light scattering instrument (0.5 /im to 10 iim). 
Figure 4.- Records of 12-hour readout. 



186 



UJ 



111 



q: 
< 

Q. 



0100 0200 0300 0400 0500 

TIME 



0600 



0700 



0800 




0900 



OC 
UJ 



111 



o: 

< 

Q. 




Figure 5.- Light scattering readout (0.5 jam to 10 jum). Cyclic events 

on day 83. 



187 



WATER ELECTROLYSIS SYSTEMS 
By E. S. Mills 
McDonnell Douglas Astronautics Company 

SUMMARY 



Three different water electrolysis units were used during the 90-day test 
of a regenerative life support system. A corrimercial unit was used for backup 
to two experimental units. One experimental unit uses a vapor feed and inter- 
mittent circulation of electrolyte and was installed inside the Space Station 
Simulator (SSS). The other unit uses a liquid feed with continuous electrolyte 
circulation and was installed outside the chamber. All three units operated 
with some degree of success during the test period. The experimental units 
provided 71. 6 percent of the total hydrogen required and 68. 3 percent of the 
total oxygen required. All units experienced failures. Some of these failures 
caused early shutdown due to inaccessibility and lack of proper parts, 
other failures were repairable because the unit was outside the chamber. This 
program indicated that additional testing of water electrolysis systems is 
needed. Greater care in hardware selection should be madcj and electrolytic 
cells should be designed to operate with greater gas-to-liquid pressure differ- 
entials. Improvements in the performance of two-phase separators are also 
required. 

INTRODUCTION 



The gas generation systems for the 90-day manned SSS test consisted of 
three different water electrolysis subsystems and a stored gas supply. These 
subsystems were required to produce high-purity oxygen for meeting naeta- 
bolic and leakage requirements and high-purity hydrogen for carbon dioxide 
reduction in the Sabatier reactor. The stored gas supply was used only in 
emergencies where excessive demand exceeded the output capability of the 
operating electrolysis units. 

The electrolysis systems used in this test consisted of a commercial unit 
and two experimental units developed specifically for this test program. The 
commercial unit was used for backup when neither experinaental unit was 
capable of meeting either hydrogen or .oxygen demands of the simulator cabin. 
This unit was identified as the Stuart unit and was manufactured by the 
Electrolyzer Corporation, Ltd. of Toronto, Canada. The other two units were 
manufactured by AUis- Chalmers Manufacturing Company (A- C) and the Lock- 
heed Missiles and Space Company (LMSC). The Allis- Chalmers unit uses a 
vapor feed and intermittent circulation of electrolyte and was installed inside 
the chamber during the test. The Lockheed unit uses a liquid supply with con- 
tinuous electrolyte circulation and was installed outside the simulation chamber 

189 




during the test. All of these systems were used with some success during the 
90-day test. All three systems were designed to provide the oxygen require- 
ments of the four-man crew and all three systems experienced some problems. 

The following paragraphs briefly describe the salient features of the two 
experimental systems and the integration of the three systems into the 
chamber design. Also described are the performances of the two experimental 
systems as well as the major problems encountered, 

SYSTEM DESCRIPTIONS 



AUis- Chalmers Water Electrolysis System 

The AUis- Chalmers water electrolysis system was designed to be an 
integral part of the MDAC-West Space Station Simulator, At its present stage 
of development, it is a nonflight systenn. which incorporates the basic principles 
and fundannentals of a zero-g flight-type systena, but not necessarily the weight, 
bulk, and detail design. Oxygen output capacity of the system is up to 10 lb/ 
day. To meet the specified requirements of 8 lb/day of oxygen, the system 
must produce 0.333 lb/hour (0. Ill Ib/hour/module), This, in turn, requires 
0. 375 lb of water be fed to the system each hour and 33. 9-amp total (an 
average of 11. 3 amps applied to each m^odule). The unit is contained in an 
enclosure approximately 24 in. wide, 24 in, high, and 18 in. deep, weighing 
approximately 220 lb fully charged with coolant and electrolyte. 

A schematic of the system is shown in figure 1. During normal operation, 
feed water is pumped to the accumulator from a supply source every 2 hours. 
The water is then fed on a pressure-demand principle through the separator 
to the electrolyte cavities in the three electrolysis modules. The water is 
electrolyzed into hydrogen and oxygen. The O2 and H2 are supplied to the SSS 
accumulators through a condenser and their respective back-pressure regu- 
lators. Water vapor, condensed frona the O2 and H2 gas, is fed back to the 
electrolysis modules. Every 2 hours the electrolyte solution (35 percent KOH, 
65 percent H2O by weight) in the modules and feed lines is circulated by a 
pump through the two-phase gas separator to remove noncondensible gases in 
the system. This purge process lasts approximately 3 minutes. Current to 
the electrolysis modules is regulated by sensing the oxygen accumulator pres- 
sure downstream of the unit to adjust the production rate to meet system 
demands. The operation is completely automatic after startup is achieved. 

Instrumentation on the front panel includes switched readout of individual 
cell voltages, module voltage, module current, system voltage, system 
current, naodule temperatures, and system tem^peratures. Pressure gages 
are used to indicate the gas and water pressures in the systenn raanifolds 
before the condensers and at their respective accumulators. Annunciator 
lights indicate when the main power to individual modules and individual 
heaters is on. Alarm lights are provided for high and low hydrogen pressure, 
high and low water pressure, high oxygen pressure, and high cold-plate 
temperature. 

190 



The unit has several safety devices and control circuits to provide the 
operator with sufficient information to take corrective action. The modules 
are protected by fast-acting circuit breakers that limit the current to 20 amps. 
Fuses are provided to protect individual circuits. The method of safety for 
the remainder of the fault conditions is a complete shutdown and isolation 
from the external line. The instant power is cut off, gas generation stops; 
hence, no change in internal pressure should occur after the unit is shut down. 
Isolation solenoids for retaining internal pressure for short periods of time 
after power cutoff prevent unbalancing of the hydrogen and oxygen pressure 
loops. The isolation valves in the inlet water lines to the modules serve two 
purposes. At shutdown, they isolate the water cavities to prevent flooding 
into the hydrogen cavities. They also provide a means of allowing all the flow 
from the circulation pump to be directed through one module during a purging 
operation by manually closing two of the three solenoids. All safety devices 
except the temperature switch operate latching-type relays which in turn 
operate the indicator lamps on the front panel. The lights remain on even 
though the fault may correct itself before the operator reaches the unit. A 
reset switch on the front panel energizes the reset coils in the latching relays. 

Lockheed Water Electrolysis System 

The Lockheed electrolytic oxygen generator is a water electrolysis sys- 
tena which was suitable for integration into and operation with the environ- 
naental control life support system of the MDAC-West Space Station Sinaulator. 
Oxygen output capacity of the system is 8 to 10 lb/day at a discharge pressure 
of 21 to 27 psig. The hydrogen discharge pressure is 9 psig. The outside 
dimensions of the system enclosure are 24 in. wide, 22 in. high, and 31 in. 
deep. It weighs 285 lb fully charged with coolant and electrolyte. 

A schematic of the unit is shown in figure 2. The concepts employed in 
the system design include the use of dual-matrix, liquid-center electrolysis 
cells with a circulating 30 percent potassium hydroxide electrolyte. The 
generating unit consists of four electrolysis modules, each containing 16 cells 
connected hydraulically in parallel and divided electrically into two 8- cell 
banks. Cells within each 8-cell electrical bank are connected in series. 
Peripheral manifolding within the module provides separate paths for electro- 
lyte circulation, oxygen and hydrogen discharge, and nitrogen purge. Differ- 
ential pressure control is used to naaintain gas-liquid phase separation across 
absorbent matrices contiguous to the electrodes. 

Electrolyte is pumped through a closed circulation loop using one of the 
two in-line magnetic-coupled centrifugal pumps; the second pump is an in-line 
spare. The electrolyte leaving the pump passes through the tube side of a 
shell-and-tube heat exchanger. Coolant supplied to the shell side removes 
waste heat generated in the electrolysis modules. Flow control valves in 
these lines are used to balance the flowmeters. Valves in the discharge 
electrolyte lines from the modules are provided so that a disabled module can 
be isolated from the circulation loop. During normal operation, these dis- 
charge valves are fully open. 



191 



Downstream of the discharge valves, the electrolyte is manifolded 
together and enters the electrolyte reservoir for return to the pump. System 
pressure is applied with a nitrogen pressurization system on the top of the 
reservoir. 

Water feed for the electrolysis process is supplied by direct injection of 
liquid water into the reservoir. A gear pump used in conjunction with a flow 
control and solenoid valve provides the proper water pressure and flow rate. 

Hydrogen is delivered from the electrolysis modules at approximately 
9 psig. Oxygen, discharged from the electrolysis modules at approximately 
9 psig, is pumped to 2 1 to 27 psig using a diaphragm pump. A pressure regu- 
lator across the pump maintains the pump suction pressure at 5 psig. 

Nitrogen purge is provided to maintain gas-liquid differential pressure 
during startup and interim shutdown. When this function is activated, either 
manually or automatically during safety shutdown, inlet and outlet solenoid 
valves in the hydrogen and oxygen discharge lines open, allowing nitrogen to 
flow through the oxygen and hydrogen chambers of the electrolysis modules. 
A micrometer valve is used to adjust the nitrogen flow rate. 

The electrolysis unit is designed to operate in an automatic mode during 
normal operation except during manual startup and shutdown. Automatic 
controls include electrolyte temperature which is accomplished by using a 
thermostat in the electrolyte discharge line from the modules. Coolant flow 
to the electronics cold plate is continuous and is regulated with a flow control 
valve. Water balance in the circulating electrolyte is maintained relatively 
constant by controlling electrolyte volunae in the reservoir. Two differential 
pressure controllers mounted on each module are set to control the hydrogen 
and oxygen pressures at 25-in. water above the electrolyte pressure in order 
to maintain gas -liquid phase separation. Each electrolysis module is pro- 
vided with a current-controlled switching regulator to control the dc current 
input. 

Safety circuits are provided to automatically shut down the system under 
abnormal operating conditions. In an automatic shutdown, electrolysis mod- 
ule power is turned off, the electrolyte pump, water feed system, and system 
reset are turned off, nitrogen purge to the modules comes on, and the cause 
of shutdown is indicated on the front panel. The shutdown signal is derived 
from nongate circuitry which continuously monitors the following safety 
circuits: (I) module tenaperatures, (2) O2 and H2 safety pressure, (3) H2 
detector, (4) electrolyte volunae, and (5) interruption of 60-Hz power. Each 
safety circuit, except item (5), has its own memory latch which allows the 
system to remenmber what type of malfunction caused the shutdown. The input 
to these memory latches is driven by the safety sensors. When an out-of- 
tolerance condition exists, the respective latch will be set. A reset condition 
can be obtained by depressing the system reset button. 



192 



SYSTEM INTEGRATION 



The Stuart unit used in this test was an upgraded version of the system 
configuration used in the 60-day test conducted in 1968. Detailed schematics 
and system descriptions are provided in reference 1. Briefly, the unit con- 
sists of an air-cooled transformer and rectifier, five Stuart electrolytic cells 
connected electrically in series, a water seal, a low-pressure gas holder for 
each gas, an air-cooled electrically driven compressor for each gas, a purifi- 
cation system for each gas, storage and reserve tanks for each gas, cell 
interconnecting piping, various protective devices, and automatic controls. 

Figure 3 indicates how the three electrolysis system were integrated to 
supply hydrogen and oxygen to the other SSS subsystems. The Stuart system 
had its own gas accumulators. Oxygen from the Stuart unit went directly to 
the two -gas control unit. Hydrogen from the Stuart unit went through a Deoxo 
purifier, common to all electrolysis units, before reaching the Sabatier unit. 
The Allis- Chalmers and Lockheed units were connected in parallel and used 
comnaon accumulators. Preceding the accumulators were Deoxo purifiers. 
The piping arrangement provided the capability, on the oxygen side, to fill the 
internal accumulator from either the AUis-Chalmers unit or the Lockheed unit 
while the Stuart unit was meeting demands of the two -gas control. The Stuart 
unit was designed and operated to maintain constant pressure in its own gas 
accumulators; any excess gas was vented overboard. On the hydrogen side, 
less versatility existed. The Lockheed unit could operate when either of the 
other two systems were providing hydrogen to the Sabatier reactor. If the 
Allis- Chalmers unit was providing hydrogen, the Stuart and Lockheed units 
were set to vent excess gas. If the Stuart or Lockheed units were operating 
and providing hydrogen gas to the cabin, the Allis- Chalmers unit had to be 
inoperative. No major problems were encountered with this lack of versa- 
tility; however, any future designs should include the ability to operate any of 
the systems without interference with any other. 

TEST RESULTS 



Allis -Chalmers "Water Electrolysis System 

Analysis of collected data has indicated that the average oxygen require- 
ment is 9. 58 lb/day. Figure 4 shows that value as well as the quantity of gas 
generated by each of the experimental electrolysis systems during the 90-day 
period. The Allis -Chalmers unit operated satisfactorily during the first few 
hours without any difficulties, then high module temperatures and cell voltages 
appeared. The amperage levels were reduced_,and the unit seemed to settle 
down to stable o|)eration, but at reduced capacity. Early on day 3, it was 
apparent that the module water pressure was very low relative to the oxygen 
and hydrogen system pressures. The low water- to oxygen differential pres- 
sure switch did not appear to be functioning as the differential exceeded 11 
psia and the operating manual indicated automatic unit shutdown would ensue 
if the water pressure was nnore than 4 psi below the oxygen pressure (ref. 2). 

193 



All corrective efforts to raise the module water pressure were unsuccessful. 
Evidently a blockage existed between the water supply solenoid and the mod- 
ules. Tests conducted subsequent to the simulator test have not identified this 
blockage. All through the early part of day 3jCell voltages tended to rise. 
Module amperage was reduced and the electrolyte w^as circulated at longer and 
naore frequent intervals. The unit was finally shut down on the morning of test 
day 3. All nnodules were flushed for long periods of time on the separate 
flushing unit to ensure the proper wetness and electrolyte concentration in the 
matrices. 

A number of attempts were made to restart the unit between days 3 and 18. 
During that period, problems were encountered with the MDAC- installed nitro- 
gen regulator and with electrical shorts in the zener diode and the bias -power 
relay. After correcting these problems, the unit was restarted on day 18. 
Again problems of high cell voltage were experienced. Difficulty was also 
experienced in maintaining the module water pressure at 2 psi or less below 
the oxygen system pressure. After trying all possible corrective measures 
without any innprovement in performance, the unit was permanently shut down 
on the evening of the 20th test day. Detailed analysis of test data collected 
from tests conducted prior to the 90-day test as well as data collected from 
the 90-day test indicated that some damage may have been done to the modules 
before the test that had caused an increase in the internal resistance of the 
modules thus causing increased voltages within each cell. This problenn was 
amplified by the high differential pressure between the module water and 
hydrogen system. The high differential pressure allowed hydrogen cross- 
leaks that limited water vapor diffusion to the electrolyte matrix. This caused 
further concentrating of the electrolyte and still higher voltages due to 
matrix drying. 

During the 98 hours of operation of the Allis- Chalmers unit, it produced 
22. 4 lb of oxygen and 2. 8 lb of hydrogen. This is an average of 57. 3 percent 
of the required oxygen for the 4-day period. This unit provided, during its 
linaited operating life, approximately 2. 6 percent of the total oxygen and 2. 7 
percent of the total hydrogen required by the SSS during the 90-day test. A 
maintenance summary is shown on table 1. 

Lockheed Water Electrolysis System 

The Lockheed unit was installed outside of the space simulator (in accord- 
ance with refs. 3 and 4) and operated on vent mode during the first 3 days; 
that is, all oxygen and hydrogen were vented to ambient. On day 3, a nylon 
fitting in module 1 was found to be leaking hydrogen. The unit was secured 
and representatives from Lockheed made the necessary repairs. Due to the 
outside installation and accessibility of the unit, repairs were accomplished 
and the unit reinstated to normal operation. The reduced performance shown 
on figure 4 between day 3 and 11 was caused by frequent unexplained shutdown 
of the 28 vdc power supply and a loose hydrogen fitting. 

The next major failure was identification of nitrogen in the hydrogen and 
oxygen supplies. Two solenoid valves were found to have lost their seals and 
were allowing purge nitrogen to leak into the oxygen and hydrogen gas passages. 
A long shutdown was required because replacement parts had to be obtained 

19^1- 



from the manufacturer. After repairs to the solenoid valves, the unit was 
restarted but capacity was reduced because of intermittent autonaatic shutdown 
by module 2 overtenaperature protection switch. This was disconnected and 
the unit seemed to perform trouble-free until day 40. Early on the morning of 
test day 40 the facility power was lost. During restart of the Lockheed unit, 
smoke was detected frona module I, This was caused by an electrical short 
from moist potassium carbonate collecting across electrodes of different cells. 
The carbonate collected from a leaking fitting above the naodule. The problem 
was overcome by using installed redundancy (module 4). Module 1 was isolated 
and the. leak repaired. 

The naajor shutdown on day 45 was caused by hydrogen leaks in the bottom 
of the modules 2 and 3. Module 1 was disassembled and new matrices were 
installed, also new temperature switches were installed. New fittings were 
installed in the bottona of naodules 2 and 3. Good operation was experienced 
until days 58 to 60 when the cooling unit, supplying chilled water to the elec- 
trolysis unit, developed a clogged filter and cooling capacity was reduced, A 
nitrogen supply solenoid valve also stuck and required cleaning. Also during 
this interval, the 28-vdc logic power supply failed. After the necessary 
repairs, the unit was restarted and operated at required gas generation rates 
for 2 days. At this time, cross-leaks were discovered in module 2. The unit 
was stopped and naodule 2 was rebuilt with new matrices and the unit was 
restarted. On day 68, more gas bubbles were observed in the circulating 
electrolyte of all modules and the hydrogen back pressure was found to be up 
to "11. 3 psig instead of the design value of 9. psig. This high back pressure 
was caused by the high venting rate of hydrogen through a fixed orifice in the 
hydrogen wet test meter. Returning the hydrogen pressure to the proper 
value eliminated most of the bubbles in the circulating electrolyte. The unit 
was observed for the next few days and on day 73 the unit was shut down to 
allow Lockheed personnel time to rebuild modules 1, 3, and 4, All matrices 
were replaced in these three modules. The unit was restarted, but naodule 3 
still show^ed evidence of cross -leaks and it was decided to operate on modules 
1, 2, and 4 for the renaainder of the test. On day 76, an electrical problem 
developed in the circuitry of module 1. This was solved by electrically cross- 
connecting modules 3 and 1. That is, module 3 circuitry operated naodule 1 
electrolysis. The unit operated at just under chamber requirenaents and with- 
out additional failures until the end of the test period. A maintenance summary 
is shown on table 2. Many of these repairs could not have been acconaplished 
if the unit had been installed inside the SSS because of the unexpected nature of 
the failures, the special skills required, and the need for safe checkout of 
performance before gas usage was allowable. 

During the 90-day test, this unit operated a total of 1, 681. 2 hours or 70. 1 
days. The unit supplied the chamber a total of 62,2 days and for 7. 9 days the 
gas generated by the unit was vented to ambient. It delivered 566, 02 lb of 
oxygen and 55, 7 lb of hydrogen to the chamber. This represents 68. 9 percent 
of the hydrogen used by the Sabatier unit and 65. 7 percent of the oxygen 
required for leakage and metabolic consunaption. Average oxygen production 
rate for this unit was 9. 1 lb/day. 



195 



The Stuart electrolyzer unit provided 23* lb (28. 4 percent) of the hydro- 
gen to the Sabatier unit and 258. 3 lb (30. percent) of oxygen to the chamber. 
Also, 15. 3 lb (1. 7 percent) of oxygen was provided from high-pressure 
storage. 

CONCLUSIONS 

All three water electrolysis systems operated with varying degrees of 
success during the 90 -day test period. The commercial unit experienced the 
least number of failures as was expected. The experimental units had more 
failures but still were able to supply 71.6 percent of the required hydrogen 
and 68. 3 percent of the required oxygen. It is evident from the test experience 
that additional development a.nd testing are required before advanced concepts of 
water electrolysis systems are ready for space applications. It is also evident 
from the test program that qualified personnel with the appropriate spare parts 
can complete very significant repairs. The Alii s- Chalmers unit, being instal- 
led in the chamber, was not accessible by highly qualified personnel nor were 
spare parts available. The Lockheed unit, being installed outside the chamber, 
was accessible for complete rebuilding of mpdules when required. Should the 
roles have been reversed, less favorable results would probably have been 
obtained on the Lockheed unit. Selection of better operating hardware and 
redesign of modules to withstand greater pressure differentials across the 
matrices would have reduced the overall maintenance of both units. Innproved 
design and performance of two-phase separators are also required. 

REFERENCES 

1. 60- Day Manned Test of a Regenerative Life Support System with Oxygen 

and Water Recovery, Part I- Engineering Test Results. NASA Report 
CR 98500, December 1968. 

2. Operation and Maintenance Manual for Water Electrolysis System. Allis- 

Chalmers Advanced Electrochemical Products Division, Greendale, 
Wisconsin 53129, June 1970. 

3. Instruction Manual for Electrolytic Oxygen Generator. Lockheed Missiles 

and Space Company, Sunnyvale, California, May 1970. 

4. Test Plan and Procedure, Operating 90-Day Manned Test of a Regenera- 

tive Life Support System. NASA- LRC contract NASl-8997, DAC 63303, 
June 1969 with changes through March 1970. 



196 



-d 




























u ^ 


IT) 


o 


O 


o 


O 


o 


o 


IT) 


o 


o 


in 


o 


in 


Hou 
Requi 


t> 


sD 


rj 


ro 


•— < 


1—1 


• 


d 


1— 1 


rj 


• 

o 


« 





m 01 
O <D 

.s 

IS 



o 



CO 



<M 



fM 



rj --H 



(M .-I 






nt 
w 







o 








-p 








n! 








—I 








rJ 








eao 










4-> 


(0 


O 




fl 


•3 






P 


TJ 


>-i 


(fl 


o 


o 


(U 


10 


H 


s 


fl 


dJ 


o 


(U 


^4 


i) 


fM 


N 


0^ 


'Q 



Hi 




o 




•i-t 




>H 




4J 




O 




» 




—4 


(» 


w 


— 1 

Rt 


o^ 


fl 


V 


a 


fH 


)-< 


•i-i 


fl) 


^ 


H 






u 

<; 



too 
nJ 
■)-> 

O 
l> 

u 

<0 



* 

0) 



o 

fl 

<u 

(D 
O 



■s 



-^ 


<a 


















n 


o 


o 










>-l 








rt 


■u 


•i-t 


















(U 


>s 


Fh 




—1 














CO 


-^ 


a> 




o 






fl 


10 


^1 




rt 


s 


CO 




^1 






(U 


—1 


o 




(U 






o 





o 


bC 






rt 
—1 


u 
o 
fl 


CO 


CO 
—4 


o 

fl 


4J 
— ) 


o 


<0 

■r) 


CO 


^4 


o 


<u 


-H 


d 


o 


V 


bO 


bo 


o 




V 


u 


O 

a 


o 

a 


O 

a 


o 

.1-1 




fl) 

fM 


bO 


a 

o 




• r-l 


a 

•XJ 


TJ 


T) 


(U 


(U 


0) 


T3 


(U 


tJ 


•n 


U 


9) 


d) 


O 


O 


U 


(U 


o 




(U 




■ r-l 


<D 


M 


(6 


rt 


«) 


pj 


rt 


j:! 


V-l 


bO 


CO 


—i 


— < 


—1 


(tt 


.-1 


!^ 


0) 


1 


^1 

3 


— < 




04 


0) 






O 


^ 


0^ 


fN 


« 


« 


rt 


U 


« 


C^ 



o 

o 
o 

0) 

u 
u 



o 



rt 

a 

o 
fl 

rt 

T) 
(U 

*> 
O 

fl 
fl 
o 
o 

CO 









fl 
O 



«• 



197 



'X3 




m <0 




U ^ 


o 




rn 


H 0) 




tf 





o 


o 


in 


.-( 


o 


o 


00 


o 


O 


O 


o 


o 


00 


«M 


I—I 


fM 


1— i 


• 
o 


•-H 


in 


o 


(M 


(M 


1-4 


I— I 


• 


O 


CO 

00 



O <U 

. a 

O :- 

2;H 



Pvl 



vO 



© 

nt 
w 

CQ 

<u 

u 

ft 

CO 



bO 



rt 


ft 




o 


ft 






Id 
(0 


(0 




u 


1> 


u 
to 

r-4 


o 


flj 

> 



ft 



ra 





to 






oc 




°£! 


C! 




^ 


•3 




w .2 


4-1 
■H 

• 1-4 




ai« 


«<H 




2^ 


O 


CO 




>s 


<u 


!>. O 


e 


j:J 


bd +> 




u 


Epo. 
sbes 


o 
w 

• iH 


4-> 


^<: 


S 


(VJ 



O 








u 




•fH 




o 




-u 


4J 


() 








() 




;§ 


]^ 


• f-l 








rl 




m 


0) 







O 


O 


(^ 
4<> 




-t> 


■ta 


!>^ 


0) 


W 


(J 


nt 


0) 


(U 


(U 


— < 


x> 


,a 


—4 


<u 


m 


0} 


w 


« 


< 


<: 



O 





























* 






























* 
















* 














1—1 
















■5S- 






* 








^ 
















CO 






* 








o 








* 
■«• 




* 




-r) 






—1 








z 








>s 


* 


•?!• 




a 






ft 








—4 








—4 


* 


ja 




rt 






ft 










* 




ft 


tn 


u 



















CJ 




■» 




ft 


(0 


.f-l 




(va 






CO 








■^ 




r-i 




d 

m 


> 

—i 




* 

■a- 

F— 1 


d 






<0 


* 




* 
* 







6 




u 


> 


(U 




2; 


■5i- 




o 
ft 


^5- 




-* 


o 




iz; 


* 
* 


S 


•w 


l4 


d 


CO 


•K- 
CD 


* 
* 


.|-> 

•1-1 




1 




aj 


w 


o 


O 


4-> 


^ 


cu 


(U 


0) 




u 




(\) 


— ^ 




•3 


•w 


ft 
bo 


CI 

.—1 






—4 


43 
o 

J > 


> 

— < 

(Tt 


o 

■ iH 


^4 
• 1-1 

o 




CO 


O 
^1 




o 


ti 


« 


o 


ft 


ri 


O 


• W 


> 


o 




* 


•V 


a 




S 


•'^i 


•i-i 


CO 


a 


o 


S 


CO 


T3 


—4 


—1 

o 




i-H 


o 

o 




■ (-1 


a 
•1-1 

nJ 


o 

4J 

o 




a> 
> 


■1-1 


..-1 


ft 

a 

(U 


• 1-1 
O 
« 


— < 



t 



u 


d 


d 

CO 


o 

•1-1 

Pi 
o 


1>^ 

•tJ 


(U 


(U 


«3 


o 


•n 


(U 


f 


o 


u 


o 

•4-1 


0) 


o 


u 


> 


(M 




M-l 

a 




4-> 

o 


J-l 
O 

CO 


—1 


o 


CO 

iz: 


o 
o 


—1 
o 


1:1 
O 


+1 

o 


• 1-1 

u 


X) 


TS 


T) 


T) 


Tf 


T! 


tJ 


Tl 


TS 


cu 


:^ 


S 


cu 
43 




(U 


<u 


(D 


(U 


rt 


(U 


<U 


(U 


CU 


(U 


h 






n 


>^ 


O 


u 


a 


h 


U 


u 


M 


o 




•4-i 


i< 


CQ 


•w 


•f-l 


n) 


fli 


o 


•w 


•w 


n! 


• 1-1 


(4 


T( 


• r.1 


• i-r 


•4-^ 


ni 


«) 


— < 


—4 


u 


r! 


(t) 


-H 


ctf 


— ^ 


(U 


d 


:i 


CJ 


3 


ft 


ft 


ft 


ft 


CO 


ft 


ft 


ft 


ft 


ft 


TJ 


.Q 


JD 


■4-1 


O 


0) 


<u 


(U 


<u 


•1-1 


<u 


<U 


<0 


(U 


<u 


Tf 


0) 


<u 


w 


« 


rt 


rt 


rt 


P 


« 


rt 


« 


Pd 


rt 


< 


rt 


« 





198 




X 

s 



:««r] :«d ^J 



<?-^i 




•i-i 

o 
u 

■l-> 

o 

Qi 
1— I 

o 

O 

!h 
0) 

a 

o 

I 

en 



faO 
•1-1 



199 



> 



> ^ lU > iU 

g 5 ! i I 

> Q # C 5 



f^ I 8 5 i^ iS 2 



j» §«D«C] 



m^A^ 



M 

K 
111 



ill 

— { \-^ 



I^hW^ 







03 
CO 

>, 

I— I 

o 

-4-> 

o 

CD 

1—1 

u 
o 

TS 
<X> 
0) 



o 
o 

I 



200 




u 
o 

t^ 

•3 

a 
•i-i 

m 

o 
•t-i 

(U 
O 

d 
a 

09 



o 

•1-1 

15 



I 

a 

09 
O 



a 

a 

Sh 

bD 
•I-I 



201 




o 
o 

CD 
bD 

C! 






fe 



(81) NOIiVll3N39 ^0 



202 



OPERATIONAL CHARACTERISTICS OF A TWO-GAS CONTROLLER 

By J. F. Harkee 
McDonnell Douglas Astronautics Company 
SUMMARY 



A system for controlling and metering the supply of atmospheric gases 
to the Space Station Simulator during the recent 90 -day manned test functioned 
successfully. A four -gas mass spectrometer was utilized to generate the 
control signals to the atmospheric controller. The controller added 862 lb of 
oxygen and 279 lb of nitrogen to the Space Station Simulator during the test. 
During most of the test, the oxygen partial pressure was controlled within 
±0. 5 mm Hg of the control setpoint and the nitrogen partial pressure within 
±8 mm Hg. The reduced accuracy of the nitrogen channel was apparently due 
to the higher than predicted cabin leakage associated with a low control loop 
gain, and can be improved by simple design modifications. 

INTRODUCTION 



One of the life support systems tested in the SSS during the naanned 
90 -day test was the two-gas atmosphere supply subsystem. This unit 
functioned by adding fixed pulses of oxygen and nitrogen to the atmosphere. 
The pulse frequency is controlled by an electronic comparator signal which is 
proportional to the difference between the sensor output and a level represen- 
tative of the preselected control point. The quantity of gas added is measured 
by counting the pulses. The operational characteristics observed during the 
manned testing are presented. 

DESCRIPTION 



The flight-type two-gas atntiosphere controller is a second-generation 
\init stemming from the controller developed for the 60-day test (reference 1). 
A feature added to the unit in addition to compact packaging and miniaturized 
electronics is the capability of the unit to accept transducer signals from 
alternate sources. This allowed the unit to operate primarily from a four -gas 
tnaas spectrometer developed by Perkin-Elm.er, or in a backup mode using a 
self-contained polarographic oxygen sensor for oxygen control and an absolute 
pressure transducer for nitrogen control, A schematic diagram of the control 
system is presented in figure 1. 

Except for the transducer circuits, the oxygen and nitrogen supply 
circuits are identical (See figure 1). A transistorized, chopper -stabilized dc 
amplifier having very low noise level is used as an integrator in each circuit. 
A 10-turn potentiometer, supplied from a regulated dc power supply, is used 

203 



to adjust the set point. Operating range of the amplifier output is 10 vdc. 
Shorting diodes across the amplifier feedback prevent integration of over- 
pressure error signials. 

The amplifier output is supplied to the control coil of a precision relay 
which is biased to approximately 6. volts by a dc power supply with a diode 
to prevent reverse current flow. Thus, error signals integrated by the 
amplifier increase voltage at a rate proportional to the signal error. As the 
voltage reaches the 6-volt bias, current conducted through the relay coil 
activates the relay. When this occurs, one pole of the relay shorts the 
amplifier output to input, and the amplifier resets to zero. Nitrogen flow is 
locked out, since both amplifiers are reset when the oxygen pulse is 
triggered. 

Another pole of the sensitive relay initiates the electromechanical timer. 
This timer opens the appropriate solenoid valve for the required pulse of gas 
and advances the pulse totalizer one count. The timer is adjustable for 
pulse durations to 15 sec. 

The flow time for an oxygen pulse was 8. 56 sec, and a nitrogen pulse 
was 9. 62 sec. The mass flow per pulse for oxygen was 2. 3 x 10-2 lb at 
the regulated pressure of 29. 7 psia, and for nitrogen 3. 83 x 10-3 lb/pulse at 
34. 8 psia. The pulse quantities were determined by the flow^ area of the 
controlling orifices, which were selected on the basis of the predicted use 
rates of about 8 lb /day of oxygen and 1 lb /day of nitrogen. 

Three oxygen source modes are available to the control unit: baseline 
mode which accepts oxygen from the flight-type electrolysis units; backup 
mode which accepts oxygen from an industrial electrolyzer; and storage mode 
which accepts bottled oxygen. Baseline operation is the primary mode, and 
is implemented by a pressure switch located on the oxygen accumulator that 
locks out the solenoid valves of the other modes when accumulator pressure 
exceeds 36 psia. Should the accumulator pressure drop below 30 psia, a low- 
pressure switch gives a visual and audio warning signal that the source 
pressure is approaching a level that will not support sonic flow through the 
metering orifice. The audio warning may be silenced by depressing an 
acknowledge switch, and the unit manually switched to the backup mode. When 
the oxygen accumulator pressure is built up to 36 psia, the unit automatically 
returns to baseline mode. In order to provide a record of the oxygen quantities 
from each source, the mode switching circuitry also switches the pulse signal 
to respective counters. 

The pneumatic portion of the unit contains the source solenoid valves, 
gas pressure regulator and regulated pressure gage, pulse solenoid valves, 
and orifices. 



204 



OPERATIONAL RESULTS 



During the initial week of the test it became evident that cabin oxygen 
partial pressure as indicated by the four-gas tnass spectrometer was not in 
agreement with that indicated by the gas analysis console (GAG). The oxygen 
level control on the atmosphere controller was decreased to bring the oxygen 
to the specified level as indicated by the GAG. In addition, efforts were 
started to verify the analysis of the calibration gas used for the GAG and the 
mass spectrometer. This analysis of calibration gases revealed that the 
oxygen content of the GAG calibration gas was about 2 percent lower than the 
vendor's certification stated. This resulted in an actual oxygen partial 
pressure in the cabin of 145 mrn Hg as compared to the desired level of 
155 mm Hg. The set point oxygen level of the atmosphere controller was 
accordingly increased and oxygeiiswafe manually added from high-pressure 
storage on day 7 of the test in order to bring the oxygen level to the proper 
155 mm Hg level. Figure 2 presents the average oxygen partial pressure 
level throughout the test, and the oxygen level perturbations of the first week 
are evident. Figure 2 also shows that the oxygen stayed within ±0. 5 mm Hg 
of the control level for the remainder of the test. Nitrogen partial pressure 
throughout the run stayed within the limits of 330 ± 8 mm Hg after the 
transients of the first few days settled out. The dips in nitrogen partial 
pressure indicated in figure 3 for days 8 and 12 resulted from leakage through 
the garbage can lid to the annulus. The dip in nitrogen partial pressure 
indicated on test days 28, 29, and 30 is attributed to leakage through the 
pass-through port while replacing the catalyst in the Sabatier reactor. The 
relatively large fluctuations in niti^ogen partial pressure are partially due to 
the leakage being considerably higher than expected. The low mass flow per 
pulse resulted in many more pulses to correct an error than desirable. The 
input circuit sensitivity was also much lower than that for the oxygen channel. 
Improvements in these parameters would result in much more accurate 
nitrogen partial pressure control. 

Figure 4 presents a record of total atmosphere pressure showing both 
the minimum and maximum pressures recorded for the day. This figure also 
reflects the dips in nitrogen partial pressure previously described. Figure 4 
also reflects the difference in operation of the solid amine unit (before day 81) 
and the molecular sieve unit (days 81 to 90). The lowering in total pressure 
is attributed to a decrease in cabin humidity and a lesser decrease in carbon 
dioxide partial pressure. 

One feature of the oxygen Circuit design caused a loss of accuracy in the 
mass flow measurement feature of the two-gas control. On periods of high 
oxygen demand, which occurred regularly during the crew's morning 
exercise period, the Lockheed electrolysis unit was unable to maintain 
accumulator pressure. The low-pressure alarm would sound at 30 psia, and 
crewmen could either manually sWitch to the backup supply, or wait until a 
lower pressure was reached. When switched to the backup supply, the 
absence of demand on the O2 accumulator results in a rapid buildup in pressure 
with automatic switchover to the primary source. In this event, the 
accumulator would again be depleted, and so on. Frequently the crew delayed 
manual switchover to the backup §upply to avoid repeated requirements, until 

^" 205 



the accumulator pressure had dropped well below that required to naaintain 
the regulated pressure to the sonic orifice. As a result, the mass flow 
indicated by the pulse counter was frequently larger than the actual flow. 
Changes in the switchover logic should be made to provide automatic change 
in both directions, with a wider band between switching points to allow longer 
periods of accumulator recharging. Reduction in oxygen channel sensitivity 
would also reduce the response to transient oxygen demands. The resulting 
loss in oxygen channel accuracy would be quite acceptable. 

No malfunctions requiring corrective action occurred at any time on the 
flight type two-gas control. A Beckman polarographic oxygen sensor was 
changed once during the mission as the original sensor had lost sensitivity. 
Since the mass spectrometer signal was used as input to the two -gas control, 
the polarographic sensor was not actually required, but was operated in order 
to obtain test experience. 

CONCLUSIONS 



The flight-type controller and sensors functioned properly throughout 
the test, having no malfunctions and requiring no unscheduled maintenance. 

The control accuracy was very good on the oxygen channel, holding with- 
in ±0. 5 mm Hg (±0. 3 percent) of the set point during most of the period. 
Accuracy on the nitrogen channel was not as good, being ±8 mm Hg 
(±2. 4 percent) over the major portion of the test. This can be improved 
considerably by increasing the input amplifier sensitivity and the flow control 
orifice size. 

The mass flow measurement accuracy was compromised by the switch- 
over logic in the oxygen channel, which required frequent manual attention 
during periods of high demand. An automatic switchover to backup supply, an 
increase in the differential pressure required to switch back, and a reduction 
in oxygen channel sensitivity w^ould improve this operation as well as reduce 
transient demands on the electrolysis unit. 

REFERENCE 

1. J. K. Jackson: Development of Automatic Controls for a Two -Gas 
Atmospheric Supply System. Presented to the 36th Annual Scientific 
Meeting of the Aerospace Medical Association, New York City, New York. 
April 1965. 



206 



ATMOSPHERE SUPPLY CONTROL SUBSYSTEM 



PERKIN-ELMER 
O2 SENSOR 



POLAROGRAPHIC 
OXYGEN SENSOR 




-SET POINT POT 
FOR OXYGEN PARTIAL PRESSURE 



BACKUP/''~N 

°2 { } 

SUPPLY V-/ 



OXYGEN PULSE 
COUNTER 



SET POINT POT 

FOR CABIN ABSOLUTE 

PRESSURE 



STRAIN GAGE 
ABSOLUTE 
PRESSURE 
TRANSOUCER 



o- 



POWER 
SUPPLY 
AND BRIDGE 
BALANCE 
CIRCUIT 




STABILIZED 

INTEGRATING 

AMPLIFIER 



SENSITIVE 
RELAY 



12-SEC 
TIMER 



, O2FROM 

I ELECTROLYS IS 

PRESSURE /I 
REGULATORV 



SOLENOID/ 
VALVE 



_prw-i 



RESET TO ZERO 



0.076-IN.DIA ORIFICE^ ^ 



OXYGEN CONTROL 



NITROGEN CONTROL 



NITROGEN PULSE 
COUNTER 



PERKIN-ELMER 
N2 SENSOR 



TSELECTORrt 
i SWITCH I 

/\ SET POINT 
"V^FORNITRO 



STABILIZED 

INTEGRATING 

AMPLIFIER 



SENSITIVE 
RELAY 



9SEC 
TIMER 



0.025 IN.. ^ 
OIA t^ 
ORIFICE 

SOLENOID « 
VALVE 



RESET TO ZERO 



SET POINT POT 

FOR NITROGEN PRESSURE 



N2 /<~V 

supplyI r 



PRESSURE f - 
REGULATORV 



Figure 1 



OXYGEN PARTIAL PRESSURE 




d 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST DAY 



Figure 2 



207 



NITROGEN PARTIAL PRESSURE 



380 










































































en 






































1 360 










































































PRESSURE, 


l^ 


^A 


t 


































r 


I 


J 


^ 


\ 


t 


^ 


^ 


y^ 




.,.„ / 


vA 


\^A 






y^ 


y 


320 






V 






v\ 


1 














^-^ 














































■V)l\ 


JIM 


JUXL 


liJJ. 


JLLLL 




JbUJL 




.1111 
















iiiL 







5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST DAY 



580 



560 



. 540 



CO 

LXJ 
0£ 



<: 



520 



500 



Figure 3 



TOTAL ATMOSPHERE PRESSURE 











































































k 


^/) 


I 


/ 




r\ 




^. 


t. 


\XIA 


,UM 


)AIL' 


' VA 


.UES 


/ 


^ 


\ 




r 


/ 


h 


f 


y 


^ 


T 


Ml 


n 


UM I 


lAin 


N 

VAI 


.UES 


:^ 




^ 


^ 






II 11 


nil 




U1.L 


nil 


i.l.JLL 


1 111 




II II 






nil 




iinj 


■ ILL 





5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST DAY 

Figure 4 



208 



IX)CKHEED 

ELECTROLYSIS SYSTHvI FOR THE 
NINETY-DAY MAIflOilD: TEST 

By Thomas M. Olcott and 
Barbara M. Greenough 

LOCKHJ]ED MISSILES & SPACE CO. 



INTRODUCTION 



The Lockheed electrolysis system for the ninety-day test was designed 
as a back-up system to operate either inside or outside the McDonnell-Do-uglas 
Space Station Simulator. The system was designed, where possible, to meet 
the same interface requirements as the vapor feed unit scheduled for use in 
the ninety-day test. '^The Lockheed unit provides oxygen automatically on 

demand at a design rate of 8.0 lb/day. startup and shutdara of the system 
can be accomplished quite rapidlj'- and are manual operations except for 
automatic safety shutdown. Safety status indicators aire provided on the 
front panel for performance monitoring. The unit is sham in Figiire 1. 

The program to design, fabricate, test and deliver a back-up electro- 
lysis system for the ninet^r^Hiay test was accomplished in four months. The 
program was initiated on 1 January 1970* The system design and system 
safety review was completed by the end of the first month. System fabrica- 
tion was completed by mid-March. Component, subsystem and system development 
checkout tests and acceptance tests were completed by the end of April. The 
hardware was delivered to McDonnell-Douglas on 5 ^'^7 1970* 

SYSTEM DESCRIPTION 

The Lockheed water electrolysis system shown in Figure 1 features 
liquid, water feed into a circulating electrolyte. This concept was selected 
because of its operating advantages in the areas of water balance, tempera- 
tvire control and effluent gas water vapor content. With direct injection of 
water into the electrolyte, rapid changes in gas flow requirements can be 
easily accommodated. The circulating electrolyte also provides the opportu- 
nity for active temperature control which iBiproves the ability of the system 
to operate over a wide variety of conditions and enhances system reliability. 
Another feature of the circulating electrolyte with active temperature con- 
trol is that the dew point of the effluent gases can be maintained below 
room temperature, thus eliminating the need for condensers and phase separa- 
tors. A schematic of the system, depicting the major elements, is presented 
in Figure 2, and the following discussion describes these elements. 




209 



Electrolysis Modules 

The generating unit consists of four electrolysis modules, each 
containing l6 cells connected hydraulically in parallel and divided electri- 
cally into two 8-cell banks. Cells within an 8-cell electrical bank are 
connected in series. Peripheral manifolding within the module provides 
separate paths for electrolyte circiilation, oxygen and hydrogen discliarge, 
and nitrogen piirge. Differential pressure control is used to maintain gas- 
liquid phase separation across absorbent matrices contiguous to the electrodes. 
Three modules are required for normal operationj the fourth module is pro- 
vided for redundancy. 

Accessory Eqiilpment 

The electrolyte leaving the modules passes over temperature sensors 
which control the electrolyte cooling and actuate the automatic shutdown 
safety circuit in the event of an overtemperature condition. The electrolyte 
then passes through a bubble separator which removes gas bubbles from the 
electrolyte which may have developed as a resiilt of dissolved gases in the 
feed water. A magnetically driven centrifugal pump is used to circulate 
the electrolyte through a heat exchanger. The flow of coolant to the heat 
exchanger is controlled by a temperature sensor in the electrolyte. A closed 
reservoir is iised in the electroljise circuit to provide system pressure 
thro-ugh the use of a diaphragm and spring. Water feed is controlled by the 
reservoir diaphragm position. As water is consiimed and hence electrolyte 
volume reduced, a signal is sent to the water feed solenoid and gear pump 
which allows water to be added to restore the initial liquid volume. The 
feed water is passed throv^h an ion exchange resin to remove ionic species 
that woiild tend to build up in concentration if allowed to enter the elec- 
trolyte. The electrolyte reservoir also includes safety functions that shut 
the system daTn in the event of a loss of electrolyte due to a leak, or 
excessive electrolyte due to a failtire of the water feed systems. 

The electrolyte leaving the reservoir is then routed to each of the 
electrolysis cell mod-ules. Gas generated by the electrolysis cells passes 
thro'ugh differential pressure controllers which maintain the correct electro- 
lyte interface at each electrode. The differential pressure controllers 
sense electrolyte pressure in the module and gas pressure in the module and 
throttle the gas effluent to maintain a gas pressure 25 inches of water 
greater than the electrolyte pressure. 

Hydrogen is delivered from the electrolysis modules at approximately 
9 psig. Oxygen discharged from the electrolysis modules at approximately 9 
psig is puraped to 21-27 psig usir^ a diaphragm puiap. A pressure regulator 
across the pump maintains the p\mip suction pressure at 5 Psig. 



210 



Nitrogen purge is provided to maintain gas-liquid differential 
pressure during startup and shutdowia. When this function is actuated, 
either raaiiually or automatically during safety shutdovnti, inlet and outlet 
solenoid valves in the hydrogen and oxygen discharge lines open, allowing 
nitrogen to flow through the oxygen and hydrogen chambers of the electrolysis 
modules. A micrometer valve is used to adjust the nitrogen flow rate. 

AUTOMTIC COMTROLS 

The electrolysis system is designed to function in an automatic mode 
during nozmal operation, except during nmnual startup and shutdown. The 
individual control functions are described in the following paragraphs. 

Temperature Control 

Control of the electrolyte temperature, necessaiy because of the 
waste heat generated in the electrolysis reaction, is accomplished by using 
a thermostat in the electrolyte discharge line from the modules to provide 
a control signal to a coolant solenoid valve. On demand, the solenoid valve 
opens to alla^ coolant to tl(M through the electrolyte heat exchanger. The 
fla-r rate is set by a flow control valve. Control of the electrolyte tempera- 
ture also provides control of the dewpoints of the generated oxygen and hydro- 
gen. The thermostat provided in the electrolyte oxygen generator has a 
switch-closure setting of 75°^. During normal operation, the dewpoint of 
the product oxygen •vrlll be no greater than 75°Fj the hydrogen dewpoint of the 
product oxygen will be approximately to°F. 

Coolant flow to the electronics cold— plate is continuous ajad is 
manually adjusted with a flow control valve. 

Water Feed 

Water balance in the circulating electrolyte is maintained by con- 
trolling the electrolyte voltme. A pair of micro switches in the electrolyte 
reservoir actuate high- and low-level s;<ritches in the water feed control band. 
A water feed cycle occurs as follows: water is consumed in the electrolysis 
raod-ules causing the volume in the reservoir to be reduced. When the rolling 
diaphragia reaches the bottom of the control band, the water feed pump is 
actuated; the water feed solenoid valve opens; and the 15 -second water 
feed timer starts. Fifteen seconds is the maximum feed time; the flow con- 
trol valve is set to deliver sufficient water in approximately five seconds. 
As water is fed to the resexvoir, the volume increases and the rolling dia- 
phragm reaches the top of the control band. At this point, the water pump 
is shut off, the solenoid valve closes, the 15-second timer resets, and a 
15-minute timer starts. This timer is set to run for five minutes. During 
this period, the water feed signal is overridden so that another water feed 
cannot occur until the timer resets. 



211 



Differential Pressure 

Two differential pressure controllers mounted on each module are set 
to control the hydrogen and oxygen pressures at 25 in. HpO above the electro- 
lyte pressure in order to maintain gas— liquid phase sepaTation. Each differen- 
tial pressure controller is essentially a valve in operating principle, with a 
spring loaded valve stem attached to a rolling diaphragm. The valve seat Is 
adjusted so that 25 in. H2O higher pressure on the gas side of the diaphragm 
than on the liquid side is required to overcome the spring and open the valve. 

Current Regulation and Oasygen Output Control 

Each electrolysis module is provided with a current controlled 
switching regulator to control the DC current input. Oxygen output is a 
direct fiinction of the current value. The current value is selected by 
automatic or manual command. These currents are maintained over a module 
voltage range of 13-5 to 17 '5 volts and a supply voltage range of 25 - 31 
volts with an efficiency greater than 75^ • 

Module k is the only module ■vrtiich can be operated in the standby mode. 
In this mode, it can only be operated at the low current value. In the on 
mode, all modules can be manually operated at either high or low current. In 
the normal automatic mode of operation, a pressure switch in the oxygen dis- 
charge line determines the high or low current value. In this latter mode, 
all modules which are on will automatically switch to the low current value 
at 27 psig and to the high current value at 21 psig. 

Safety Circuits 

Safety circuits are provided to automatically shut down the system 
under normal operating conditions. In an automatic shutdown, electrolysis 
module power is turned off, the electrolyte piJmp, water feed system and 
system reset are turned off, nitrogen purge to the modules comes on, and 
the cause of shutdown is indicated on the front panel. 

The following safety circuits are provided: 

Module Tempejreiture - A temperature sensor is located in each module, 
in contact with an end electrode. These thermostats have two switch- closures: 
one at 85°F and the second at 100 F. The 85 F point provides a warning sig- 
nal; the 100 F point signals automatic system shutdown. Any one of the four 
temperature sensors can actuate the shutdown. 

Gas Pressure - The oxygen and hydrogen discharge lines from the 
modules each contain a pressure switch set to actuate automatic shutdown 
if the pressure reaches approximately 13 psig. 



212 



Electrolyte Volurne - Switches located in the electrolyte reservoir 
are actuated if the electrolyte volime in the reservoir exceeds a 3^ change 
in the total electrolyte volume. 

Hydrogen Detector - A hydrogen detector is located directly over the 
electrolysis modules and will signal automatic shutdawi if the hydrogen 
concentration reaches O^Qp. 

Power Interruption - The loss of input power to the unit, even if 
raomentarj"-, will automatically put the system in the shutdown mode from 
which it will have to be manually restarted. 

CHECKOUT TEST RESULTS 

During checkout tests of the system at Lockheed two problems evolved. 
One of these was with the closed reservoir and the other was with the nitro- 
gen purge system. These problems will be discussed in this section. 

The uait utilized a zero-gravity bubble separator and closed reser- 
voir water feed system. These two components made the design completely 
gravity independent. The bubble separator, which was the key element in the 
zero-gravity operation had been successfully bench tested for ninety days. 
HdW-ever, the closed resenroir water feed system was a new component . During 
checkout tests of the -unit, the spring in the closed reservoir caused an 
xmexpected pressure increase which damaged the bubble separator membrane. 
The spring was operating in the region of buckling, which produced an 
erratic spring rate. To correct this, it required a redesign and fabrica- 
tion of a new spring and repair of the bubble separator. The delivery 
schedule did not allow sufficient time for this, and hence an available one- 
gravity bubble separator and water feed system was substituted. This unit 
consisted of a reservoir with floats for water feed and system volume safety 
control. Electrolyte pressure was achieved by applying a controlled nitrogen 
pressure to the top of the reservoir. 

The spring for the closed reservoir wa^ subsequently increased to a 
larger diameter and a nylon spring guide was provided. The bubble separator 
was reworked and these two components have been successfully bench tested in 
an electrolysis system located at Lockheed. 

The second problem that occured during the developaent testing was 
mixing of hydrogen and oxygen in the nitrogen piirge line. This was observed 
when gas samples were being obtained at various points in the system. The 
original configtiration for the nitrogen purge supply was a solenoid supply 
valve branching to two nitrogen supply lines with check valves. These lines 
supplied pressure to the hydrogen and oxygen passages of the electrolysis 
modules . The mixing of hydrogen and oxygen occurred at a point between the 
two check valves and was due to the fact that the check valves were not 
providing a positive seal. The sitviation was corrected by providing two 
nitrogen supply solenoid valves, one for the hydrogen and one for the oxygen 
gas passages. Check valves with a high cracking pressure were also provided 
in these lines. After these modifications were made, the problem did not 

213 



reoccur . 

ACCEFTMCS TEST RESULTS 

At the conclusion of the checkout tests conducted at Lockheed, a 
continuous 100 hour acceptance test was conducted. During this acceptance 
test, the system operated successfuHj-- in a continuous hands-off mode. 
Oxygen vras supplied to an accumulator which was venting at a rate of 8.0 
lb/day. The unit automatically cycled from high to low current mode as 
required to achieve an 8,0 lb /day oxygen production rate. The performance 
results of the 100 hour acceptance test are presented in Table I, indicating 
the required and demonstrated characteristics. In all cases, the gas purity 
exceeded the requirements and there was no admixing of hydrogen and oxygen 
detected. 

NXNETY-DAY TEST RESULTS 

The electrolysis system was delivered to McDonnell-Douglas on 
5 I''fe.y 1970* I'lie unit \ra.s installed outside of the cabin simtilator to be 
used as a back-up system. 

Test Installation 

During installation, two additional problems developed. The first of 
these problems was the failure of the electrolyte to coolant heat exchanger. 
The probable caiise of this failure was fatigue of the heat exchanger due to 
rapid cycling of the coolant solenoid valve. The temperature sx/itch that 
controlled the coolant solenoid was changed diiring the Installation because 
the original sv;-itch did not meet the ORI requireu^nts. The neir switch was 
bi-meta3J.ic and did not provide a sharp closure which caused the solenoid 
valve to chatter, resulting in hydraulic hammer on the heat exchanger. The 
problem was rectified by replacing the heat exchanger and modifying the 
control circuit to filter out the switch noise. Ho subsequent problems were 
experienced with the heat exchanger. 

The second installation problem occtxrred during a loss of 28 VDC 
supply pcRiTer to the unit. I'/hen this occiirred, the residual cell voltage 
was impressed on the nitrogen purge solenoid valve, which prevented them 
from opening. This problem was rectified by adding a relay which opened 
the circuit to these valves during a loss of input pcwer. 

Ninety— Day Test — Lockheed System Status 

The status of the Lockheed electrolysis system is presented in 
Figiore 3« The system operated for TO days during the ninety-day test period. 
The bulk of this operating time v;-as spent in the primary mode during which 
the unit was supplying hydrogen and oxygen to the chamber. Some periods of 
operating time were spent in the standby mode where the system was operating 
but was not providing oxygen and hydrogen- to the chamber. For twenty of the 
ninety days, the system was turned off for corrective maintenance. 



2li|- 



Pailiire Analysis 

During the ninety-day test, failures occvirred which required correc- 
tive action. These failures are presented in Table II. The table does not 
include failures of test support equipment unless they resulted in a sub- 
sequent electrolysis system failure. The period of time that the imit was 
off is also indicated on the table. This was not the time required for 
maintenance since, on some occasions, time was required to obtain new parts. 
None of the failxxres that occurred during the ninety-day test were major in 
natTjre, nor did they indicate a need for alteration of the basic concept. 
The failures primarily were associated with the accessoiy equipment and 
could have easilj' been avoided if reasonable development test time had been 
available prior to delivery of the unit. The only failure involving the 
electrolysis cell modules was caused by a problem with equipment that the 
electrolysis cell interfaced with. This occurred when the back pressure on 
the hydrogen supply was increased to a point near the matrix breakthrough 
press\n:*e. This was done periodically and eventually resiilted in a matrix 
failure. The applied pressure was slightly less than the overpressure switch 
setting, however, breakthroxjgh occurred at a slightly Ics^rer pressiire than was 
anticipated due to the cyclic na,ture of the pressure pulse. This problem 
would not have occurred if the overpressure switch setting had been reduced. 
Loss of current control on the J'Jth day caused the unit to supply oxygen at a 
rate slightly below the 9.6 lb /day required by the chamber but at a rate well 
above the 8.0 lb /day design point. 

CONCLUSIONS 

The results of the ninety-day test have indicated that the circulating 
electrolj'te system offers some operational advantages. The system demonstra- 
ted the ability to operate automatically^ for long periods of time with no 
operator adjustments required. The system was also able to respond to wide 
vsiriatious in gas demand. Active teiaperature control provided stable opera- 
tion with no effluent gas water removal required. As a result of the 
experience gained in the ninety-day test, a number of design improvements 
have been identified which would increase system reliability and maintain- 
ability for zero-gravity operation. These improvements include: 

o Provisions for replacing circulating fluid loop assemblies without 
breaking Integrity of fluid system'. A multi-man system would 
consist of several fluid loop assemblies. 

o Minimi7.ing lines and fittings through additional internal Eiani- 
f olding . 

o Reduce sensitivity to downstream hydrogen and oxj-gen pressiure 
pulses. Subsequent to the ninety-day test, cells have been 
built ahd tested with increased matrix support which prevents 
matrix damage when a gas breakthrough occurs. This eliminates 
the need for matrix replacement. Additional work is being 
conducted on higher brea.kthrough matrix supports. 

Based on these design imx)rovements, it is felt that this system is a primary 
candidate for future space electrolysis system applications, 

215 



CO 
EH 



IX! 



H O 



% 

3 
^ 



Ei 



I 






O 

CO 



Pi 
CM 

V 



Pi 

cvi 

V 






* 

O 
o 



0\ 



ir\ 
O 

o 



<; 




ft 




p5~ 




h4 


t-J-i 




l>- 


o 


• 


• 


<Tn 


00 


ON 



v?J. 


>>a^ 


H 


or, 


• 


• 


o 


ON 




o\ 



H 

B PI 

Q g 

o o 




ITN 



H 

o 



g g 






216 



g 

H 



O 
O 



o 

I 

Q 



o 



?5 



H 

TO 

I 



n 



1^^ 



EH 
E4 



O M 

o o 



p 



E5 






o 




i 



ii 

CO s 

o o 



s 



CO 



I 

Q 



g 
a 

H 



TO 
H 
CO 

>4 



H 



R^ 
a"^ 



EH 
CO 



Eh 






I 






E2 



o 
o 




o 



P 



« 



s 

H 
E^ 



CO CJ 






> O 

H CO 

pq CO 



a 
o 




MHO 



E5 






H 
^ 




s 

i 

H 
O 

I 



O 






s 

CO 



s 



n H 



to 



CO 
CM 



OJ 



S 



d 

g 



9 



CO 
H 



OJ CV] 






CO 



trs 



s 




217 




Figure 1.- Lockheed electrolysis system. 



218 



TO CHAMBER 



No PURGE 



^Itl 



Q— I — Q>-» 



DIAPHRAGM 
PUMP 



02 



30% 
KOH 



^ 



VENT 

ELECTROLYTE 
PUMP 



MODULES (4) 



TO CHAMBER 



N, PURGE 



VENT 



BUBBLE 
SEPARATOR 



H.X 



COOLANT 



WATPP V^* 



IT 



IT 



CLOSED 
RESERVOIR 



WATER 
FEED CONTROL |0N 

EXCHAN6jE 



Figure 2.- System schematic. 



FROM 
CHAMBER 
WATER 
SUPPLY 



PRIMARY 



STANDBY 



OFF 




5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST DAY 
Figure 3.- Ninety-day test Lockheed system status. 



219 



EVALUATION OF A FOUR- GAS MASS SPECTROMETER 

USED FOR ATMOSPHERIC CONTROL DURING THE 

NINETY- DAY TEST 

By Michael R. Ruecker 

Perkin-Eltner Corporation 
Aerospace Systems Division 
Pomona, California 91766 

SUMMARY 



The design and performance of a Mass Spectrometer Atmospheric Sensor System 
which was utilized for monitoring and control of the atmosphere of a manned 
space station simulator during a 90 day test is reviewed. The instrument 
was a modified Two Gas Atmosphere Sensor System which was operated with a 
new closed loop electronics control system for improved long term stability. 
Based upon calibration verification data taken during the 5-day and 90-day 
runs, the instrvmient was demonstrated to hold its calibration within 1% for 
nitrogen, 2% for oxygen, and 3% for carbon dioxide for a period of 132 days. 
It also monitored water vapor partial pressure. The output signal from the 
oxygen channel was employed by an atmosphere control system for maintaining 
the oxygen partial pressure of the space station simulator. The instrument 
demonstrated its ability to perform reliably and its potential value as 
equipment for ECS applications . 



INTRODUCTION 

In 1965 a phased program aimed at the development of a mass spectrometer 
system for monitoring the major constituents of a buffered two gas atmos- 
phere as well as the primary metabolic products of respiration was initi- 
ated with Langley Research Center. The Two Gas Atmosphere Sensor System, 
a single focusing magnetic sector mass spectronteter , evolved from this 
program, and was capable of continuously monitoring nitrogen, oxygen, 
carbon dioxide, and water vapor. An engineering test model and four 
prototype units were fabricated on this program. One of these units is 
shown in Figure 1. These instruments have been employed in several 
applications for atmospheric and respiratory measurements in various 
laboratories, a space station simulator, and two undersea habitats. One 
of these applications was in conjunction with the 60-Day Manned Space Cabin 
Simulator Test in 1968. At that time the Two Gas Atmosphere Sensor System 
was operated externally to the Space Cabin Simulator with a laboratory 
vacuum system, and sampled the cabin atmosphere through a capillary-bypass 
inlet system. 




221 



In the most recent application, the subject of this paper, one of the 
original instruments was refurbished, equipped with updated electronics, 
repackaged with a close coupled ion pump and a direct entry sample inlet 
system, and mounted inside the Space Station Simulator where it monitored 
the partial pressures of oxygen, nitrogen, carbon dioxide, and water vapor. 
The output signal of the mass spectrometer's oxygen channel was provided 
as the input to the atmospheric control system which controlled the oxygen 
partial pressure. The performance of the combined system was more than 
adequate to hold the oxygen partial pressure within the limits required 
for constant physiological functioning of the crew. 



PRINCIPLES OF OPERATION 

The Two Gas Atmosphere Sensor System is a single focusing magnetic sector 
mass spectrometer that is designed to provide four simultaneous outputs 
which are proportional to the partial pressures of N2, 02» C0_, andH20. 
The fundamentals of the operation of the mass spectrometer are diagrammed 
in Figure 2 . A small quantity of the gas sample to be analyzed is 
continuously introduced to the mass spectrometer through a molecular inlet 
leak. The characteristics of this leak allow each constituent of the 
sample to flow through the leak independent of the other components . The 
resulting partial pressures within the ion source are proportional to the 
corresponding partial pressures in the sample environment. 

The ion source performs the function of ionizing part of the gas to form 
charged particles which are then acted upon by the electrostatic and 
magnetic fields within the instrument. Ionization is accomplished by 
bombardment of an electron beam which is derived from a hot wire filament. 
The ions are repelled from the ionizing region, focused by an electrostatic 
lens, and passed through the ion source exit slit into the magnetic sector. 
A permanent magnet provides a uniform magnetic field through which the ion 
beam passes within the vacuum envelope. The ions are deflected into 
circular arcs by the magnetic field, their radii being proportional to the 
square root of the mass to charge ratios of the ions. Since all the ions 
of interest are singly charged, the radii are proportional to the square 
root of mass (vari) . Consequently, the ions are dispersed as they leave 
the magnetic field and are collected by four Faraday cage type collectors 
located along a focal plane. The collectors are attached to single piri 
feedthroughs that pass the current through the vacuxim envelope to four 
electrometer amplifiers that amplify the small currents to provide output 
voltages which are proportional to the ion currents. The output signals 
are therefore proportional to their respective partial pressures. The 
internal vacuum necessary for operation of the analyzer is maintained 
by a suitable high vacuum pump, which is connected to the mass spec- 
trometer by means of a pump tube. 

The Two Gas Atmosphere Sensor mass spectrometer analyzer assembly is shown 
in Figure 3. The vacuum envelope, permanent magnet, single pin feedthroughs 
and the pump tube are clearly visible. The multipin feedthroughs that are 
visible in the ion source housing provide the voltages that operate the ion 
source filament and focusing electrodes. 

222 



REQUIREMENTS FOR THE 90-DAY TEST 

The requirements for the 90-Day Space Station Simulator (SSS) application 
were a modified Two Gas Atmosphere Sensor to monitor the partial pressures 
of nitrogen, oxygen, carbon dioxide and water vapor. The principal require- 
ments are summarized in Table 1. 

The instrument was to be located within a specified volume within the SSS 
and to give continuous outputs within a specified tolerance for the entire 
90-day period without requiring recalibration . In order to provide informa- 
tion for engineering evaluation of the instrument's performance, a method 
of making calibration verification was required. The instrument was to be 
provided with the necessary support equipment to maintain its Internal 
vacuum through a power failure. Dual outputs were necessary for internal 
signal monitoring by meters as well as voltage outputs to be monitored by 
the computer system external to the simulator. 

TABLE 1 



Requirements for 90-Day SSS Atmospheric Sensor 
Monitored Species: H2O, N2, 0„, and C0„ 

m/e 18, m/e 28, m/e 32, and m/e 44 

20 torr, 500 torr, 200 torr and 120 torr, respectively. 

Nominally 10 Ibf/in^ abs or 517 torr 



Monitored Masses: 
Full Scale Ranges : 
Total Pressure: 
Configuration: 



Limited size consistent with available space and 
commercial support components. 



Operating Controls: None for normal operation. Inlet system valving for 

initial setup and calibration verification. Power 
on-off, ion pump, and emission current adjusts. 



Maintenance ; 
Outputs : 



None 

Internal: four meters. 

Remote: four buffered, linear, zero to 5 volt. 



Performance Monitors: Anode current, ion pump current, and battery 

voltage. 



Sample Inlet: 
Nominal Accuracy: 

Environment: 



Sample transport line with 3 inch H„0 head. 

±2% of full scale for N2 and O2 . 
±3% of full scale for CO2 
±5% of full scale for H2O 

Compatible with operation in the Space Station 
Simulator 



SYSTEM DESCRIPTION 

The description of the 90-Day SSS Atmospheric. Sensor is facilitated by 
considering its major system components which are: first, the sample inlet 
and calibration inlet system; second, the mass spectrometer subsystem 
including its vacuum pump; and third, the support electronics subsystem 
which includes the electronics required to operate the analyzer and ion pump, 
as well as Lhe output circuits. A block diagram of the system is shown in 
Figure 4, and can be used for reference in the following discussion. The 
sample and calibration inlet system shown in the upper left hand comer of 
Figure 4 is shown in greater detail in Figure 5 and the front panel of the 
system is shown in Figure 6 . 

To simplify the system description, each part of the system referred to has 
been assigned an index number as shown in Figures 5 and 6. Sample gases 
enter the inlet system from the 1/8 inch sample line at the sample inlet 
point (1) . The sample gas then passes through a needle flow control valve 
on the front panel of the instrument (2). After passing through the flow 
controlling valve, the sample gas goes to the mode selector valve (3) which 
determines the mode of operation, that is, operating in the calibration 
mode or the normally operating sample mode. After passing through the mode 
selector valve, the gas is filtered by a two stage inline filter (4) . On 
the sample outlet, corresponding sets of filters (5) are present. The gas 
mixture then passes through a sample flowmeter (6) which measures the rate 
of gas flow through the instrument and therefore allows the pressure drops 
through the inlet system to be checked. After passing through the flow- 
meter, the sample travels past a total pressure transducer (16) and out the 
sample vent (17) . Between the double filters the gas passes through the 
variable leak valve (7). This variable leak valve is fitted with a 
temperature control system. The heater switch (8) controls the heater for 
the inlet valve. The calibration gas mixture is stored in a pressure tank 
(9) with regulator (10) . Passing through the regulator, the sample gas 
goes to a protection shutof f valve (14) , to a needle flow control valve 
(15) , and then to the selector valve (3) . Part of the gas to be sampled 
(either the sample gas or the calibration gas) passes through the restric- 
tion in the leak valve and through a small diameter line (11) into the mass 
spectrometer (12) and finally to the ion pump (13) . There is a roughing 
valve (25) located within the analyzer chassis for initially pumping down 
the instrument. The conductance of the variable leak valve can be adjusted 
by means of a slotted screw adjustment (28) on the front panel. The ion 
currents coming out of the mass spectrometer are detected and amplified by 
four electrometers. The electrometer outputs go to the output meters (26) 
and also to buffered outputs. The zero levels of the electrometers can be 
checked by pressing the press-to-test button (27) , which cuts off the ion 
beams. The main power to the mass spectrometer is provided by a 28 V dc 
power supply, and requires a 115 volt ac input. 



22ij- 



There is a front panel switch (18) that controls the operation of the 28 volt 
power supply. Other Items on the front panel are the ion pump meter switch 
(19) , and the ion pump current meter (20) . These monitor the current flowing 
to the ion pump from the high voltage supply and therefore, indirectly 
monitor the analyzer pressure. There are two other meters on the front panel 
of the Analyzer Control Module. One of these is the battery voltage indica- 
tor (21) . This indicates the stage of readiness of the emergency batteries 
that are used for powering the ion pump in a power off situation. The other 
front panel meter is the anode current meter (22) . This meter measure the 
anode current and gives an indication of the sensitivity at which the source 
is being operated. The anode current may be adjusted only in open loop mode 
by the .anode current adjustor potentiometer (23). The mode of operation, 
open or closed loop, is controlled by a selector switch (24) on the front 
panel . 

An important feature of the system is the closed loop mode of operation 
which automatically compensates for any coimnon mode variations. The four 
electrometer outputs are scaled to provide signals that are all proportional 
to pressure with the same volt per torr sensitivity and are simmied to give a 
"total pressure" signal. Since the four components of interest comprise 
essentially all the atmosphere, this signal can be compared with the out- 
put of a total pressure transducer, which is reflecting the true pressure 
seen by the sample inlet system. The resulting error signal represents the 
sensitivity error of the mass spectrometer. This signal is fed back to the 
emission regulator that controls the level of ionizing electron current in 
the ion source and, thereby, the levels of the ion currents which are 
detected at the collectors. In this way the summation of the partial 
pressures is held at the prevailing ambient pressure level and, consequently, 
common mode variations due to such factors as changes in the inlet leak 
conductance or ion source sensitivity are eliminated. This method of 
operation represents, a significant improvement in mass spectrometers design 
and allows a high level of accuracy to be maintained for a long period of 
time. 

Other elements of the system, which are shown in Figure 4, are the power 
supplies that provide voltages to the ion source, the ion pump and its high 
voltage power supply, the power supply system, the front panel control and 
monitoring functions, and the output buffer amplifiers. 

The complete 90-Day SSS Atmospheric Sensor is shown in Figure 7 and the 
internal construction of the upper and lower bays is shown in Figures 8 and 9, 
respectively. The upper bay contains the mass spectrometer, ion pump, their 
support electronics, the sample inlet and calibration inlet systems, and the 
calibration gas supply. The lower module houses the main power supply, the 
battery pack and charger, the buffer amplifiers, output and nmnitoring meters, 
and the buffer amplifiers and pressure transducer power supplies . 



225 



CALIBRATION 

The Atmospheric Sensor was calibrated by use of a calibrated gas mixture of N2, 
02» and CO2 • In order to calibrate the instrument as nearly as possible to 
the expected operating conditions, the calibration gas was admitted to a 
laboratory inlet system in which the pressure was held at 10 Ibf/in^ abs 
(517 torr) , and from this reservoir it was introduced into the mass spectrometer 

inlet system. The volt per torr sensitivity at the electrometer amplifier 
output of each channel was computed and this information was utilized to 
adjust the summing resistors so that the current arriving at the summing 
junction of the summing operational amplifier from each channel has the same 
ampere per torr sensitivity. Then the gains of the buffer amplifiers are set 
so that the proper full scale value for each channel is achieved at five volts. 
During the dry gas calibration the pressure was exercized between 400 and 634 
torr to verify that the channels were tracking pressure. This is a ±22.6% 
pressure variation which is much greater than the expected variation of the 
space station simulator atmospheric pressure. The final calibration data over 
this pressure range is shown in Table 2 . 

TABLE 2 
Table of Calibration Errors at Final Calibration 



Pressure 


Error 1 


N2 


02 


CO2 


400 torr 
517 torr 
634 torr 


+0.37% 
-0.01% 
-0.29% 


-0.85% 
+0.01% 
+0.58% 


-2 . 86% 
+0.31% 
+2.87% 



The water vapor channel was calibrated by allowing the inlet system to sample 
laboratory air and comparing the H2O electrometer output with the partial 
pressure, as computed from the relative humidity indicated by a wet bulb - dry 
bulb Mason's form hygrometer. Since the instrument was sampling at one atmos- 
phere during this test, the variable inlet leak valve was closed down to main- 
tain the normal internal partial pressures. The water sensitivity was compared 
with the nitrogen sensitivity as determined from the air composition and this 
data was utilized to set the water vapor channel summing resistor and buffer 
amplifier gain. 



OPERATIONAL RESULTS 



During the 5-day test run the calibration of the Atmospheric Sensor was 
verified twice by admitting a calibration gas sample. During the first veri- 
fication the gains of the buffer amplifiers for the dry gas channels were 
reset. The oxygen buffer amplifier eain had somehow shifted during the process 
of shipment. Inspection, and installation. The other buffer amplifiers were 

226 



very close to their proper values. The data from this calibration verifica- 
tion and a second one taken later during the run is shown in Table 3. In 
both cases the error is less than one percent on all dry channels . 

During the 5-day test it was found that the water vapor channel was reading 
high compared with the Cambridge Dew Point Hygrometer. The dew point indica- 
tor was reading 11.3 torr while the mass spectrometer was reading 23.1 torr, 
with a buffer amplifier output of 4.68 volts. Just prior to the end of the 
run the buffer amplifier was adjusted to give an output of 2.82 volts 
based upon an 11.3 torr partial pressure and a desired system gain of 20 torr per 
5 volts. This correction gave the proper water output, but it did not correct 
the summing resistor for the water channel, which was also apparently in 
error. One effect of this adjustment is seen in the data presented in Figure 
10. This shows the error between the sum of the partial pressures as 
indicated by the mass spectrometer, and the total cabin pressure as measured 
by the Wallace-Tieman gage. During the 5-day run the sum of the partial 
pressures agreed with the total pressure within one percent or better except 
for the final reading, which was 2.9 percent low. This final value was taken 
after the water vapor channel was readjusted. This additional 2 percent 
error amounts to an error of 10.5 torr at 525 torr total pressure, which is 
very nearly equal to the 11.8 torr error that existed in the water output 
prior to adjustment of the buffer amplifier. 

This error results from the action of the closed loop, which makes up for 
the erroneously high H2O electrometer amplifier output by dropping the 
ionizing current to achieve the correct total pressure. Reduction of the H„0 
buffer gain led to a low value for the summation of the partial pressures. 

TABLE 3 
Results of Calibration Verification During the 5-Day Test 





ERRORS, PERCENT 1 




N2 


O2 


CO2 


Ipp 


INITIAL 
FINAL 


+0.23 
-0.91 


+0.23 
-0.71 


+0.47 
-0.70 


+0.23 
-0.84 



During the 90-day test the Atmospheric Sensor perfonned without malfunction. 
Five calibration verifications were run during the course of the test and the 
data from these is presented in Table 4. This data shows that the mass 
spectrometer maintained its calibration within very close tolerances. The 
last adjustment of the instrument was made on 30 April, 1970. Therefore, the 
analyzer maintained its calibration on N2> 02> and C02 within 0.9, 2.1, and 



227 



2.7 percent, respectively, for a period of 132 days. The sum of the dry gas 
partial pressures remained within 0.84 percent during the same period. It is 
difficult to evaluate the performance of the instrument by any means other 
than the calibration verification data. Typical output data for the instru- 
ment is shown in Figures 11 through 13. This data was taken from the computer 
reduced data obtained on the MDAC Low Speed Data Acquisition System at 1800 
hours on each day of the test. This time was selected because it was consid- 
ered the most "normal", with the least unprogrammed activity, and should give 
a more representative picture of the cabin atmosphere from day to day. 

Figure 11 shows the variations in the oxygen and nitrogen partial pressures ; 
Figure 12, the variations in the carbon dioxide and water vapor partial 
pressures; and Figure 13, the variation the cabin pressure, the sum of the 
partial pressures, and the difference between these two values. A cursory 
review of the data has indicated that the fluctuations in the partial pressures 
are usually accounted for by specific known events that occurred within the 
SSS . The oxygen partial pressure was controlled within a total variation of 
2.9 torr or better than ±1 percent. The total pressure variations are much 
wider primarily because of a lower gain in the nitrogen make-up portion of the 
atmospheric control system. The variations in the carbon dioxide and water 
vapor partial pressures reflect changes in the status of the solid amine and 
molecular sieve CO2 scrubber systems. The summation of the partial pressures 
is consistently low because of the incorrect summing resistor in the water 
channel, as predicted by the last data point taken during the 5-day test run. 
The indictment of the water channel is made even clearer by comparing the 
correlation between the water vapor output and the error in the summation of 
the partial pressures . Note that whenever the water vapor level goes up the 
summation of the partial pressures goes down, ^nd vice versa. This is 
exactly what was expected from a detailed analysis which was made of the 
interchannel effects of an incorrectly established summing resistor. 

TABLE 4 
Results of Calibration Verification During the 90-Day Test 









Error , 


percent 




DATE 


TIME 


O2 


N2 


GO2 


Ipp 


6-13 


1315 


+1.1 


+0.1 


-1.5 


+0.4 


6-18 


1902 


+0.7 


-0.4 


.0 


0.0 


7-8 


1135 


+0.9 


-0.6 


+0.8 


0.0 


7-13 


1346 


+1.3 


-0.5 


+0.6 


0.0 


9-9 


0250 


+2.1 


-0.3 


+2.7 


+0.1 



228 



During the course of the 90-day test it was found that the CO2 output of the 
mass spectrometer was not in agreement with the infrared analyzer. Consequent- 
ly, on 21 August, 1970, a portion of the gas utilized to make the initial 
calibration of the mass spectrometer was sent to the laboratory that made the 
original mixture analysis. The results are shown in Table 5. 

TABLE 5 
Comparison of Calibration Gas Analyses 



Component 


Mixture 7130P | 


1/30/70 


8/21/70 


Nitrogen 

Oxygen 

Carbon Dioxide 


66.166 

31.271 

2.544 


66.336% 

31.632% 

2.012% 



Note that the calibration for CO2 changed by more than 20 percent. If the 
later calibration figures are utilized, the agreement with the infrared 
analyzer is very close. There is no reason to suspect that the calibration 
gas changed during this period, and therefore, it must be concluded that the 
original calibration was in error. 

At the conclusion of the 90-day test the Atmospheric Sensor was shut down and 
returned to Perkin-Elmer Aerospace Division where it is now being operated on 
laboratory ambient atmosphere for a period of 180 days . 



CONCLUSIONS 

The Atmospheric Sensor was shown to be a reliable and accurate instrunent for 
monitoring nitrogen, oxygen, carbon dioxide, and water vapor during the 
course of the 90-Day Manned SSS Test. It demonstrated its capability not 
only to monitor these constituents but to provide outputs that could be 
utilized by an atmospheric control system for regulation of the primary 
atmospheric constituents of a closed environment. The closed loop operating 
mode controlled the sensitivity of the mass spectrometer so that it could 
operate for a period of 132 days without a calibration. The accuracy of the 
outputs was affected by the initial calibration, which was found to be in error 
because of a faulty calibration technique in the case of water vapor, and an 

inaccurate calibration gas mixture in the instance of carbon dioxide. These 
procedural matters have been rectified and should allow the Atmospheric Sensor 
to perform to its full capability in future applications. 



229 



The 90-Day Manned SSS Test was intended to prove out equipment for application 
to future space stations. It is therefore important to assess the feasibility 
of reducing the size, weight, and power of the Atmospheric Analyzer to levels 
which are compatible with a flight program. A contract under the direction of 
NASA Manned Spacecraft Center is currently in progress for. the development of 
a flight qualified Mass Spectrometer Atmospheric Sensor System (MASS) as well 
as a modified version to be used as a respiratory gas analyzer as part of the 
M-171 Metabolic Analyzer, which will be used in Skylab in 1972. A photograph 
of the instrument is shown in Figure 14. 

These imits are fully self-contained and require only a sample inlet and bypass 
line, a small diameter vacuum line to outer space for initial roughing of the 
mass spectrometer, system power, and command functions for the ion pump mass 
spectrometer electronics, open-loop/closed-loop control, and selection of one 
of the dual ion source filaments. The system is fully protected against 
operation at excessive pressures and provides status indicator outputs on all 
important functions that can change during operation. The inputs and outputs 
are fully isolated and protected and the instrument has sample inlet heaters 
and ion source temperature control for improved performance. 

The design is fully compatible with Apollo and Skylab environments including 
a 38 Ibf/lW^ abs over pressure requirement. The atmospheric monitoring 
version of this instrument measure the partial pressures of hydrogen, water 
vapor, nitrogen, oxygen, carbon dioxide, and hydrocarbons in the mass range 
50 to 120 amu. The final configuration of this system weighs 21 pounds, 
requires 19 watts of power during normal operation, and has a cylindrical 
enclosure with a diameter of 7.2 inches and a length of 12.5 inches. The 
first design verification test unit of the MASS ±s scheduled for delivery to 
NASA MSC in November 1970. 



250 




Figure 1.- Two gas atmosphere sensor system. 



251 



SAMPLE INLET 



ANODE 



OBJECT SLIT 
ION BEAM 




FILAMENT 

ELECTRON BEAM 

ION FOCUSING LENSES 



MASS SEPARATOR 
(ANALYZER) 



DETECTORS 



PUMP OUT 



Figure 2.- Principles of mass spectrometer operation. 



252 




Figure 3.- Two gas sensor mass spectrometer analyzer assembly. 



235 



P-f CTRANSDUCER) 



BUFFER AMPS 



110 VDC POWER INPUT 



NITROGEN 




Figure 4.- Atmospheric sensor system block diagram. 



25ii- 



CALIBRATION FLOW 
NEEDLE VALVE 




Figure 5.- Sample and calibration inlet system schematic flow diagram. 



255 




22 8 21 18 



Figure 6.- Atmospheric sensor front panel. 



236 




0) 

U 
O 
03 

03 

o 

•fH 

0) 

m 
o 

S 

15 

O 
15 



CQ 

O 

cc 

a> 
o 

Pi 
m 

I 
O 

c» 
i 

« 



25T 




X. 






c. 



258 




•'*'-_■»*','* 



/« 









."*, 




t® 







7, . ^>. HKbA . 



, .-f- 










I 



o 

« 




259 



a. 

I- 

o 

—J 

< 
1- 

o 
a 



a. 
cc 

■ o • 






o 



a. 
o. 
W 
<J - 



— r- 



+ 



O 



© 



G 
O 



I 



— CM 



CO 



— r- 

-a- 



>- 
< 



<o 




A 




-M 




o 




+-> 




«3 




0) 




^ 




S 




to 




m 




(U 




;^ 




a 


• 
-4-> 


1— 1 


CO 


rt 


0) 


• iH 


-w 


-4-> 




^< 


t>. 


tA 


oi 


O. 


-o 


•S" 


> 


e! 


Jfl 


o 
•i-i 


(U 


■^ 


5 


a 




s 


•S 


3 


!L4 


en 


3 


(X) 


tJ 


43 


(U 


-M 


u 


«f-l 


s 


o 


m 


Pi 


CO 


u 


u 




u* 


u 


F-( 


rt 


d 


a 


1=", 


a 


o 

-M 


o 




U 




• 

o 




1-H 




0) 




$-1 




a 





1X4 






2^0 











































I 




-J 
o 
































\ 


4 
































^ 






































































J 




(rt 


































^ 




































1 




































i 










1 


























>■ 


Nn 




































A 








1 


























j 




































< 




































r 


> 










\ 
























>/ 














k 




















\ 


V 










1 




lO 




















I 










i 




_/ 




















>» 


\ 








K 


Vi** 


o: 




















1 


^ 












UJ 




















< 














o 

/ 






















{ 












/ 


/ 






















i- 


__ 


— — 




— — 




/ 


















O 
























\ 






































!> 










































a: 








CM 


= 




















^ 






g- 


-*- 






- 




i 


















<^ 








cu 








> 
















\ 


■^ 




































\ 


































/ 






































~~- 


M 


^ 


































< 


^ 
































r 


"^ 










0* 




















1 


















'\ 






































































\ 


o 






















> 












/ 




! 




















\ 

^ 


E> 










/ 










u 














\ 


N. 












/ 








2 

3 


is 

-UJ 

IS- 














\ 


\i 






i 


\,' 










C 






CI 


N. 


' — ' 












^ 










< 




Q 


F^ 


r.< 














( 










UJO 








/ 


^ 














L 




















< 


















^ 


^ 














l/" 


^ 


















\ 














'^ 














■ 








\ 














c 
u 


> 


c 


> 


s 


} 


c 


s 




< 


! ' 


r 


c 


d C 


> a 


> ^ 


^ 


f 


J c 



en 
+-> 

I 
o 

OS 
Q 

faD 
fl 

CO 
01 
;-i 

CO 
CQ 
CD 
U 
O. 
I— I 

•r-l 

!h 

& 

a> 
fafl 
o 

s 

73 



bo 
I 






caaoii siinssaad iviiavd 



2^1 







































o 

§ 

o 

2 

s 
s 














\ 
























\ 














I 
























\ 
















"^ 






















/ 




"" "t 






























M^ 


r - 












--^ 
















^ 




-^ 






0) 




' ■ 


































5? 












































^ 
































1 
o 






■V 


\ 






























Oi 




.-- 






\ 


















^ 










43 








\ 


\ 
















1 












1 






/ 
















/^ 












1 




< 




















^- 


-\ 










1 






V. 


k 




















. 






- 










_,^ 


t» 
















"s 


» 






CO 


























/ 










u 

0) 

a 


i 






















— -- 




y 
















r- ■ 


-^ 

















7 


















y — 


— . 


:^ 














*v 


>» 



















^ 
















s 


s 




































-— 


J 








■e 








.ff 
















oti 


^ 












fs! 






^ 


•^^ 






















)> 








o 





























^ 






















> 














> 








p* 












: 












« 


s, 










> 
u 


J 












\ 












■^ 


;>• 






















V 


r 








^ 


^ 










C4 

1 

T3 












. 




-^ 












"^ 


















Nx, 


, 


















,^ 


/ 


















V 














< 






















,^ 


:/ 












/ 


J' 




















> 














<x<; 


> 








g 












\ 




















— ■ 


— ■ 


1 


^ 
















^ 


\ 




















a 


















I 
















^ 


t 


o 






























•e 


~i. 






53 












r-* 




-<v 


Si 












«: 


-^ 






u 



















J 
















^ 


r 


1 

• 








1 


< 


'^' 














^ 


■ — 




■^ 


















••^ 


■^ 


^ 












"^ 




^ 






<U 
















r 






















E 














/ 


f 


































( 


















^ 






|X4 














\ 


s. 
















N 


Sii 






















^ 
















X 


B 




(M 


.-1 


S 


0* 


03 

C 


> 




HOI} 


3ur 


fff 

SS: 


5 :: 


MXU 


4 f 


J I 


1 »■ 

X 


c 


i " 


■^ a 


3 





2i4-2 




o 




^ 




s 




m 




m 




o 




u 




a 




1— 1 




ctJ 




-M 




O 




-M 




a> 




,£5 




+j 




O 




-M 




cn 




(U 




u 




3 




to 




CQ 




0) 




U 




a, 




r-H 


+j 


nl 


en 


•r-< 


01 


t 


-M 


rrt 


b 


a 


cd 
T3 


•^^ 


1 


o 


O 


c 


o> 


o 
•1-1 


(U 
X5 


rt 


+J 


a 


SP 


B 




•n 


(-1 


rn 


^ 




T3 


(1> 




Xi 




-M 




<M 




o 




c 




o 




en 




•iH 




^ 




oi 




a 




a 




o 





CO 

u 



CMHOU sanssaad iwiiavd 



2^4-5 



■" f '■: <■:<> y :■ .-V •>< •'(>:■ '\i \ Vi'df iiAfii 




Figure 14.- Flight qualified mass spectrometer atmospheric sensor system 
for atmospheric and respiratory monitoring. 



•^ s\v,i->v ;••>.-,.'-•.> %-'*<■>■'*.'•-;';:-■ -fV is A ,' . 5. 



:-'^;?V^-:« :^;?/>«-^ 5 v-iaSW?^^;-^^;^-:,-. ..M/^/f ■.'':,: 



2lA 



UESIGN AND OEEMTIOH OF A WASTE MAUAGEMEKT STSTEM FOE 

FECAL COLIiECTION MD SAMPLING DURING THE 90-DA.Y 

MANNED SIMULATOR TEST 

Bjy Courtney A. Metzger 
Aerospace Mfedlcal Research Laboratory 
Wright-Patterson Air Force Base, Ohio 

SUMMAET 



A component designed for the collection, processing, and storage of feces 
and toilet tissue aboard aerospace vehicles has heen fabricated and successfully 
tested. This system is a type similar to the "Dry John;" however, this new 
design extends the useful life of the prior design by use of a replaceable liner 
assembly (liner, slinger, motor, and filter), sized for approximately 200 man- 
days acciiraulation. The filter prevents contamination of all downstream lines 
and permits changing of the liner without contamination of the cabin. Other 
features of the unit are a quick-acting slide-valve assembly, a fecal sampler, 
and a disinfectant dispenser. 

INTRODUCTION 



Various means of collecting and processing feces and other solid wastes in 
zero-gravity environment aboard spacecraft are being investigated in a number 
of programs. Several of these have been supported by the Aerospace Medical 
Research Laboratory, both in-house and on contract. One such program was for 
the development of a four-man, 60-day waste managanent system (ref . l) , which 
was used in a simulated space chamber (ref. 2). This system called "Dry John" 
in turn was used as a base-line for an improved version, called Extended Life 
Dry John (ELDJ), which was used in a recently completed four-man, 90-day test 
sponsored by NASA and conducted by McDonnell Douglas Astronautics Company 
(MDAC). This report describes the components and operation of the system. 
Results obtained during the 90-day test are presented by MDAC in paper no. 19 
of this symposiiim. 

EfSTEM DESCRIPTION 



A photograph of the system is shown in figure 1. The individual components 
of the system are Identified in the system block diagram of figure 2. These 
components are a seat to support the user, a slinger- shredder to spread feces 
on the liner where they can be quickly vacuum dried, a unit for dispensing dis- 
infectant onto the feces for odor and bacteria control, and a removable liner 
which extends the useful life of the system. Items not part of ELDJ, but 

2ij-5 




necessary for it to function, are a blower to provide fecal transport and odor 
control, a vacuum system to dry accumulated feces, an odor filter, a secondary 
bacteria filter, a power source (il-00 Hz, 3-plis,se, 115/200 volt), and a quick 
disconnect. 



SYSOIEM OPERATION 



The first step in the operation of the ELDJ is to open the seal valve under 
the seat. This action, by means of interlocking solenoids, starts the sllnger 
and blower, opens the blower line frcm the system, and closes the vacuum line 
from the system. Cabin air is immediately drawn into the container, thus pre- 
venting backflow of odor, bacteria, or debris from the container to the cabin. 
The user then occupies the seat, which is contoured according to guidelines in 
reference 3- This seat contour provides comfortable support to the user as 
well as a means of indexing himself over the storage container. Upon defeca- 
tion, the stool is transported by gravity and airflow (in zero gravity, air is 
the only means of transport) to the flat surface of the slinger. Here the stool 
is slung outward and shred by the slinger tines then spread on the interior sur- 
face of the storage container liner. Each layer of feces spread in this manner 
is. densely packed and sufficiently thin to be dried rapidly by the subsequently 
applied vacuum. Used toilet tissue is dispensed with in the same manner as 
feces; however, the tissue will not shred If it is dry. After tissue disposal, 
a predetermined quantity of disinfectant is injected onto the slinger by 
pressing the disinfect switch. The slinger then sprays the disinfectant over 
the spread feces. Any dry tissue that might have become entangled on the 
slinger tines will be wet by the disinfectant and then dislodged from the tinesj 
hence, the disinfectant provides a secondary benefit of helping to clear the 
slinger tines in addition to the primary one of reducing bacteria and odor. The 
blower which is run during usage for fecal transport also helps to control odor 
and bacteria by drawing gases associated with defecation through a filter before 
these gases can diffuse into the simtilator environment. When finished, the user 
closes the seal valve under the seat. This action, the reverse of the first 
step, stops the slinger and blower, closes off the system from the blower, and 
opens the system for vacuum drying of the contents. 

If a fecal sample is needed, a cap covering the sample port is removed and 
the fecal sajapler (see fig. 3) is inserted into the ELDJ before usage. This 
action of inserting the sampler opens the sampler cavity in which feces are col- 
lected as they are slung toward the liner. Conversely, the action of removing 
the sampler closes the sampler cavity in which the feces sample has been col- 
lected. The sampler, as it is being removed from the ELDJ, is drawn into a 
plastic bag which is then sealed. This bag is fitted with a valve to permi.t 
gas sampling or vacu\na diying of the contents, if required. After sampler 
removal, the cap is replaced on the sampler port. 

The ELDJ components for collecting feces, distributing them with a sllnger- 
shredder, and providing airflow for odor and bacteria control and for transport 
of feces, are similar to corresponding Dry John hardware. However, to extend 
the useful life of the present unit compared with that of the Dry John, the 

21^6 



present xmit is provided witli a replaceable liner sized for approximately 
200 man- days of usage, hence the name Extended Life Dry John, or ELD J. 

To allow convenient installation or removal of the liner, a split container 
is used. A single quick-acting V-hand clamp joins and seals the two container 
halves. Likewise, other quick disassembly devices are used at all "break 
points." When the liner is removed and discarded, the slinger and filter are 
also removed and discarded because they will have been subjected to fecal con- 
tamination. The motor will also be discarded because the cost and weight of 
additional components which would be required for salvage approximate those of 
the motor itself. 



■EEFEEEECES 

1. Cooper, L. ; Fogal, G. L. ; and Murray, R. W. : Waste Management in Manned. 

Space Vehicles. [Preprint] 670855, Soc. Automot. Eng. , Oct. I967. 

2. Anon. : 60-Day Manned Test of a Regenerative Life Support System With Oxygen 

and Water Recovery. Pt. I - Engineering Test Resiilts, I^C-62295 (Contract 
Ko. MSw-1612), McDonnell Douglas Astronautics Co., Dec. I968. (Also 
Available as MSA CR-9850O. ) 

3. Kira, Alexander: The Bathroom - Criteria for Design. Bantam Books, I967. 



2^7 




2kd 



^ ' Fj^s 






Solenoid 

m 



Timer 



/'Tines 
Slinger/piate 
l-Motor 




Quick (iiscounect 



f 

Mr return 

to cabin 



%lit container 

SoiidsS storage 
V-&and elamp 



OebriB and bacteria 
filter 



Secondary 
bacteria filter 



Vaeuunj 



Vent 



SoieJK)i<fe 
interiocked 
with seal 
valve 



Figure 2,- ^stem block diagram. 



e%9 










'^ i 
















250 



WASTE MANAGEMENT SUBSYSTEM 

By J, K. Jackson and R. E. Shook 

McDonnell Douglas Astronautics Company 

SUMMARY 

The waste management subsystem included the commode, urine collector, 
and urine phase separator. The commode was provided by the Air Force 
Aerospace Medical Research Laboratory (AMRL) and manufactured by General 
Electric. The urine collector was an Apollo type with built-in flush water 
injector, provided by NASA-MSC. The urine phase separator was built by 
MDAC for this program, and included automatic pretreatment injection. 
Operation and crew acceptance of all units w^ere generally adequate except the 
urine phase separator, in which the polyurel^hane irrlpeller was dissolved early 
in the test by an accidental injection of concentrated pretreatment solution. 
Subsequent use of the urine collection system required the use of gravitational 
forces for phase separation. The comraode required liner replacement once ; 
during the mission, on day 44, and was used 319 tim.es. 

INTRODUCTION 

The design guidelines for wa'ste management during the 90-day test 
included: minimum crew handling of w^aste products following elimination, 
effective control of odors and bacterial contamination to the cabin, conven- 
ience of operation and maintenance, and design for zero-gravity operation.. 
A "Dry John" j^ommode which had been built for AMRL by General Electric 
had been preyiously used by MDAC in the 60-day test. This unit included a 
slinger-type collector with air induction of feces, a spherical bowl for stor- 
age, and sequencing valves for vacuum dehydration between uses. Thisiunit 
had performed satisfactorily according to the above guidelines, but was 
expected to have inadequate capacity for the 90-day test resulting from the 
increased duration and the predicted increase in residual fecal solids because 
of the improved diet. An improved model was therefore built which included 
a replaceable liner in the collector bowl, a sampling device, improved con- 
trols and valves, and a disinfectant injection system. 

During the previous 60-day test, urine pretreatment solution had been 
inaccurately added. A urine collection unit was therefore built by MDAC to 
provide automatic addition and to adhere to the requirement for null-gravity 
capability. 

EQUIPMENT DESCRIPTION 

The waste management system is shown schematically in figure 1. A 
description of the commode and associated equipment is included in paper 

251 




numiber 18 of this symposium. In addition to this equipment, a toilet paper 

collection receptacle was provided as a contingency in the event adequate 
collection capacity was not available in the commode. This was connected to 
the vacuum system in parallel with the commode and used a porous paper bag 
such as is used for a disposable vacuum cleaner collector. When filled, these 
bags were sealed and placed in the dry waste storage container. 

The urine collector operated on an air entrainment principle, similar to 
the fecal collector. A centrifugal separator, using a porous polyurethane 
impeller, was used to separate the air from the urine. The air then passed 
through a charcoal filter for odor adsorption and was returned to the cabin by 
a small blower. Pretreatment fluid, which was a solution of sulfuric acid, 
chromic oxide, and copper sulfate, was stored in a reservoir and proportion- 
ally added to the urine stream. The urinal was located adjacent to the fecal 
collector and could be used separately or in conjunction with the commode. 
An Apollo type urine collector with provisions for flush water injection was 
provided by NASA-MSC. 

Several methods were provided for handling of waste and garbage. Excess 
water remaining from^ preparation of some food items was added to other 
highly contaminated water including concentrated sodium hydroxide solution 
from the microbial sensor and periodically pumped overboard. Wet garbage 
was sealed in standard No. 2 metal cans after treatmient with 8-hydroxy 
quinoline sulfate for bacterial control. The disposable dishes were stored in 
aluminumi boxes having tight-fitting covers after being similarly treated with 
bactericide. Food packaging material was baled and wrapped with aluminum 
foil, in which the meal packs were originally wrapped, and stored in cabinets. 
A large aluminum container was provided for other dry waste, including 
filled toilet paper bags. This container was fitted with a sealing cover about 
12 in. in diameter and could be vented to the SSS annulus periodically if 
desired to remove odors. 



TEST RESULTS 



The commode operated very satisfactorily during the 90-day test. Table 1 
presents commients on commode operation. Table 2 is a summary of com- 
mode performtance. During use of the first liner, all toilet paper was put into 
the commode. The liner was considered full and was changed on day 44, at 
which time it appeared to be about two-thirds full. The used liner was stored 
in the unused pass -through airlock for the balance of the mission. During use 
of the second liner, the crew was instructed to place used toilet paper in a 
separate receptacle. At the end of the test, the liner appeared to be about 
one-third full. Separate collection of toilet paper appears to be desirable for 
extension of liner life. 

One significant operational error occurred. On day 38 one of the crewmen 
noticed the Wescodyne disinfectant was not being injected into the commode 
after use. Subsequent checks revealed that a nitrogen valve controlling pres- 
sure to the disinfectant tank had been closed since the start of the test. Sub- 
sequent injection was satisfactory. The tank was refilled once during the run. 

252 



The urine collection system operated until test day 6 w^hen the time-delay 
relay controlling pretreatment addition remained energized, allowing a large 
quantity of pretreatment solution (sulfuric acid, chromic oxide, and copper 
sulfate) to enter the phase separator. This dissolved the polyurethane foam 
impeller. Subsequent to this, urine ■was collected in a beaker and measured, 
and pretreatment solution was manually added. Until day 41, this urine was 
poured directly into the urine accumulator. At this time, the test crew 
installed a direct line from the urinal to the urine accumulator to allow a 
direct transfer. Subsequently, the urine was poured into the urinal and flush 
water was then manually added. Pretreatment was added in 15 ml anaounts 
as required by urine output. Antifoaming agent was added at the urine 
accumulator when the VD-VF systemL was operating. 

The wet waste was stored in 42 No. 2 cans. The test crew was instructed 
to pass cans out of the chamiber on the regular weekly pass-out if there were 
signs of bulging or indications of potential rupture. As a result, 23 of the 
filled cans were passed out during the test. Saving these at room environment 
resulted in only 5 developing discernable bulges. One of these was opened and 
found to contain a high concentration of potassium hydroxide, apparently 
included in a wiping cloth, and much resulting corrosion. Contents of other 
cans have not yet been examined. However, it appears that the crew was 
innproperly instructed in material to put into the cans, and possibly overly 
cautious in passing them out. It was felt that, under no circumstances, should 
a chance be taken of a can rupture inside the SSS during the test. 

Used food trays were stored in five of the aluminum boxes provided. A 
total of 2, 408 trays were used, with a maximum number of 521 in one of the 
boxes. No problems w^ere encountered w^ith this disposal method. 

Dry garbage stored in the big container weighed 17. 65 lb, including four 
bags of toilet paper having a total weight of about 3 lb. A fifth toilet paper 
bag was in the receptacle next to the commode, nearly full. 

No record is available of the amount of stored food wrappings, although 
no problems were encountered with their storage. Reuse of the original 
aluminum foil provided convenient, satisfactory, and safe overwrap for 
packages of used food wrappings. 

MAINTENANCE SUMMARY 



Table 3 summarizes the major maintenance items on the waste manage- 
ment subsystem. Most of the repairs required on the commode and urine 
collector have already been discussed. The leakage of the trash container 
caused some concern because a permanent correction could not be made. As 
a result, venting of the can to the annulus was done only occasionally Avhen a 
noticeable odor was generated in the can. On one or tw^o instances, signifi- 
cant loss of cabin atmosphere occurred when the can was left venting 
to the annulus. This was detected by the resulting loss in cabin 
pressure and corrective action was taken w^ithin a few hours to close 
the vent valve. 

255 



CONCLUSIONS 



Design of the commode unit ■was generally satisfactory. It performed 
well and was accepted by the crew. 

Problems encountered ■with the urine collector enaphasize that a device 
handling a dilute solution of a very corrosive fluid must also be qualified to 
survive failure modes in which much more concentrated solutions are 
improperly introduced. 

Handling of garbage and other general waste products requires further 
study. Perhaps the data on types and quantities produced will serve as a 
basis for system design to reduce the quantities and provide more effective 
means for handling them. 



2^ 



n) 
Eh 



o 

W 
ft 

o 

w 

Q 

o 

o 
u 

o 

w 

:^ 
:^ 

o 
u 



c 
o 

nJ 

a 
o 
O 



a 
w 
o 

■<-> 

i-H 
T3 
0) 

P4 

■X} 

*i 
Ck 
nJ 
73 
<! 

o 






u 

W 
C 

•H 
Q 



<u .q 



u 

•H 
CO 

tJ 

p 

Rj 



U 

a> 

u 



o 

■u 
O 

13 



CO 



CO 

W 

a 

o 
o 

Pi 

u 



cr 
W 



u 

CO 

o 

o 

I— I 
n! 
C 
O 

CO 

a 
o 
o 

O 



o 

CO 



T3 



m 



u 

CO 







o 

CI. 

CO 

ClJ 

a 

(U 
.£) 
Fh 
O 

CO 
•X3 

< 

O 

^4 
■!-> 
fl 
O 

u 

1—1 
o o 
O fx, 



<u 
u 
<u 

CO 



o 
U 

DO 

(i 

O 

u 

93 

r- 1 

a 
(« 

CO 



(0 



<0 

Q 



T3 

bo 
.J 



o 

y 
nJ 

<T 

<J 

M 
u 
v 

43 

O 

O 

U 



bo 
G 

U 



bO 

(O 
•H 



CO 
<u 

CO 



o 
u 
y 






4) 
U 

u 



CD 



in 

CO 


O 



t3 



y 



XI 

a 

4) 
EO 
CO 



2 ^ 






CO 

hi 

a 
O 



pj 


cr 


> 


y 


a> 


<o 


u:| 


Pi 




«<-( 




o 


Q 


bO 


<J 




XJ 


bo 
c< 


05 


O 


4<« 


y 
•r! 


I— 1 
P. 


ct3 



o 



CO 

X 

a 

M 
u 



09 

(l) 

Q 






o 

y 
CO 

i 

CO 

o 

p 



■)-> 
c4 

-a 

y 



;h 
o 

-u 

y 



U 



o 

CO 
l-H 
T3 

O 

<: 

CO 

a 
o 

T3 
(U 
•■-I 

Q 

OJ 
;h 

X! 

E-i 

u 

0) 

bo 

CJ 

r-l 

to 



o 

> 

a 

Ph 

d 
y 

!-i 
<U 
ft 

o 

A 






■■-> 

O 
XI 

<u 
a. 

cd 

ft 

(U 
1-4 
••-I 

O 

bO 

•1-4 

T3 

.3 

y 



u 



a 

rH 
O 

!> 

pq 
u 

(U 

a. 
ft 
c 

0) 

y 

(0 

ft 



3 
ft 




o 

XI 

<; 

•i 
u 

0) 

<^ 

ft 

(U 
1-4 
• 1-4 

o 

H 

iB 



CM 

^4 



255 



to 

4) 




rO 


CO 








vO 




H 




O 


CO 


vO 


r4 


00 


vO 


v^ 




• 


, 


a 


• 


• 


• 


• 


t-j 


1 cr^ 


cr^ 


ro 


vO 


CO 


00 




CO 


nS 


1 <— t 


(M 




(M 


in 


r~ 






■4-i 


1 CO 

















in 



00 
00 



o 



rJ 


^ 


=«=: 


bO 


u 


O 


(U 


u 




^ 


H 




■<* 




^ 





* 
















in 


in 


o 






CO 




1 vO 


t* 


(M 


pj 


o 


-* 


^ 


vO 


00 1 


1 (^a 


o^ 


, 


• 


• 


a 


a 


■ 


• 1 


1 * 


• 


in 


o 


in 


(va 


r^ 




m 1 






1— 1 




I— 1 


en 


Tf 











U 



CO 
O 






00 



00 

o 



o 

sO 



00 



NO 



o 
ro 









o 

O 
O 













lU 












N 












(U 






5 












n 






h 






■!-> 




p 








O 

d 

o 
O 


^ 


to 

•V 


a 

o 








•k 


.— i 


^ 






to 


;h 


o 


^1 rQ 






13 


(U 


w 


(1) H 


13 
<U 




o 


f 


-^ 


(4 ^ 


to 

p 

to 


to 


CO 
(0 

to 


■1-1 


o 


al W 
raps 


>- 


<u 


O 




*i 


o Eh 


(d 


m 


fH 


O 


0) 


(U 


Q 


P 





B 


^ 


h 



03 

o 

t4 



o 
Eh 



u 

0) 

(4 
o 

O 



(i 
Q 
u 

tn 



a 
u 

< 



<i 
Q 
u 

ft 

to 

(U 

to 

p 

a 

I 



(4 
Q 
u 

ft 

I» 
<u 
m 

P 

a 

I 
••-I 

a 



(1) 

p 

5 



bO 






60 
(4 

< 



p) 
d} 
to 

(Q 
03 

(U 

P( 
-p 

0) 
i-H 
■H 
O 
-P 

«M 
O 

0) 

u 



256 



(0 

u 

I 



OJ lf\ 


ITvO 


OJ 


o 


K> 


li\ 


m 


o 


fOv 


H^ 


CO lA 


K> 


o o 


O iC\ 


VD 


s 


O 


O 


o 


tOv 


-4- 
H 


O 


a^ 


!^ 



O tH 

o fl 

^ EH 



H H 



H H 



KN OJ 



CO 



OJ 



I ^ 



OJ 



s 



pi 

<U 
^^ 
c3 
ft 



m -p H 



IS iJ 



•H 
-P 
-P 

•H 

tlD 
liH P 

m 3 



-P 
P 

•H 
^ . 

•H -H 



P 
O 


H 



O 
•H 



cj a 0) p 



0) 
CQ 

bO 



^ 




>> 

p> 







-g 




•H 


^ 




o5 




> 


^ 




p 


U 


•H 


Dl 


rM 




<U 


P> 
O 




3 


■p 


•H 


03 


0) ^ 
H ft 


-p 


p 


rH 


(U 




pi 


t) 


■ri 


O 


g OJ 


§ 


0) 


0) 




3 ^ 


"^ 


-d 


pS ^ 


-p 


c 


fl 


o 


q > 


o 


•r 




p 


^5 


Q) 


CQ 

r! 


R** 


•H 


Tj -d 


5 


n:i 


^^ 


g^ 


<U (U 


to 


Ti 


-d ^ 


J^ 


p> p) 


•d 


(U 


0) g 




o o 


-d 


H 


o <u 




<U 0) 




H 


CS CQ 




^^ 


p! 


•H 


H m 




5 


"in 


ft 03 




o o 




0) 


<D 




o o 




« K 



O 

Vi 

CQ 

o 

•H 

ta 
O 

•H 



g 

O 
o 

H 
O nd 



H 

Q M -r! 
a Si -P 

_■ P<_. 
<d O "d 
(U Q) 

bOpi 



O 

H 
cd 
P> 

CO 

a 

•H 

& 



o 

•H 
P> 
O 



& ' - 

a gj p 

(U Cl fH 

p> o " 



O CM 



O 
O 



ft 

a 

•H 




•H 

•H 

-d 
li 



H 



O 

ch 

•H 
P" 



P> 
O 

a o 

o 03 

•*^ 1 

-d o 

(U o 

•H & 

d ° 

•d p 



p> 

CQ 

•H 

O 
P> 



2 
t 

o 
o 

& 



ft 



-d 



o 

p 



0) 
H 



-d 

p 
o 

o 
o 



p 

•H 



o 

■8 

OJ 
H 
H 
O 
o 

<u 

•H 



u 
Pi 

•H 

t 
o 
o 

CQ 
EH 



257 



WASTE MANAGEMENT SUBSYSTEM 



TO WATER 
RECOVERY 
SUBSYSTEM 



FLIMH WATER 

(FROM WASH WATER SYSTEM) 



CAMNAIR 




METERING 

ram 



V 
OVERBOARD 
VACUUM VENT 



Figure 1 



258 



FOOD MANAGEMEHT PROGRAM 

IBy J. S. Seeman and D. J. l^ers 
Mcltormell Douglas Astronautics Company 



SUMMARY 



The food, provisions available to onboard crewmen during the 90-day test 
consisted of a primary freeze-dried menu, supplementary snacks, frozen dinners, 
glycerol (sweetener), and a small amount of ice cream. Packaging, storage 
accommodations, supporting equipment, and acceptability of the food supplies 
are discussed. Recommendations for food programs for future long-term space 
missions are provided. 



IB1TR0DI3CTI01I 



In response to frequently reported negative reactions to food provisions 
for previous crews of long-term missions and simulations involving confinement, 
MDAC established the policy, early in the planning phase of the 90-day test, to 
select and provide food from the standpoint of acceptability. Acceptability 
was felt to be a fxxnction of menu diversity, mission dxxration, and initial reac- 
tion to the aesthetics of food cons-umption: flavor, color, consistency, and 
aroma. 

This approach permitted the collection of information relevant to resolu- 
tion of the question of whether attention to these factors could eliminate nega- 
tive reactions to food provisions or whether such negative reactions could be 
expected to accompany all future long-term operational or simulative confinements.- 

PROCEDURES 

Known processors of food provisions for space missions, or those known to 
have the capability, were contacted and requested to submit samples of their 
products. A list of potential suppliers was obtained through the cooperation 
of cognizant personnel at the U.S. -Army, latick Laboratories. From this review 
of products, their availability, diversity, and projected ability to meet cri- 
teria on microbiological control, Oregon Freeze-Dry, Inc., Albany, Oregon, was 
selected as the principal supplier of onboard food. Table 1 represents some of 
the freeze-dried menus that were provided. 

Req^lirements placed upon the supplier of freeze-dried, uncon^iressed food 
consisted of: Microbiological control consistent with NASA/Aniny requirements, 
vacuton packaging, a 10-day menu cycle, and 2500 kilocalories/man/day . HASA/Army 
microbiological specifications were adhered to except for deviations on total 
aerobes (raised from 10 to 20/g) and total streptococcus counts (raised from 

259 



DAYl 2, 531 TOTAL CALORIES 
BREAKFAST -926 CALORIES 



TABLE 1 

REPRESENTATIVE MENU 

FREEZE-DRIED 

LUNCH -748 CALORIES 



DINNER -856 CALORIES 



(49)* ORANGE JUICE 


(23) PEA SOUP 


( 1) SLICED BEEF 


(57) GRAPENUTS WITH MILK 


(56) CRACKERS (6 CRACKERS) 


(70) WITH GRAVY 


(73) SUGAR 


(14) HAM AND GREEN BEANS 


(42) MASHED POTATOES 


(30) DICED HAM 


AUGRATIN WITH RICE 


(35) CHOPPED BROCCOLI 


(31) SCRAMBLED EGGS 


(%) PEANUT BUI ILR COOKIES 


(26) COTTAGE CHEESE WITH PEARS 


(91) TOAST (2 SLICES) 




(76) BROWNIES 


(75) JELLY 




(74) MARGARINE (1/2 TSP) 


(68) MILK(8 0Z) 






DAY 2 2, 460 TOTAL CALORIES 






BREAKFAST -654 CALORIES 


LUNCH -733 CALORIES 


DINNER -1,0/3 CALORIES 


(55) STRAWBERRIES 


(20) CONSOMME 


( 4) SLICED HAM 


(28) CREAMED BEEF 


(56) CRACKERS (6 CRACKERS) 


(59) NOODLES WITH CHEESE SAUCE 


(90) ON TOAST (3 SLICES) 


(9) BEEF WITH RICE 


(33) ASPARAGUS 


(94) CHOCOLATE MILK (6 OZ) 


(24) CARROT-RAISIN SALAD 


(85) CHOCOUTE PUDDING 




WITH AUVIONDS 


(74) MARGARINE (1/2 TSP) 




(95) DATE FILLED OATMEAL 






COOKIES 




DAY 3 2, 563 TOTAL CALORIES 






BREAKFAST -697 CALORIES 


LUNCH -724 CALORIES 


DINNER -1,142 CALORIES 


(53)* DRIED OR STEWED PRUNES 


(64) CHICKEN NOODLE SOUP 


(19) SHRIMP COCKTAIL 


(61) RALSTON WITH MILK 


(56) CRACKERS (6 CRACKERS) 


(3) DICED CHICKEN 


(73) SUGAR 


(13) CRAB IMPERIAL 


(71) WITH GRAVY 


(91) TOAST (2 SLICES) 


(27) SWEET CORN 


(58) NOODLES 


(75) JELLY 




(36) CARROTS, DICED 


(68) MILK(8 0Z) 




(77) COCONUT MACAROONS 


(93) CHEESE SCRAMBLf 




(74) MARGARINE (1/2 TSP) 


DAY 4 2. 458 TOTAL CALORIES 






BREAKFAST -698 CALORIES 


LUNCH -934 CALORIES 


DINNER -826 CALORIES 


(48) GRAPEFRUIT JUICE 


(16) TUNA ALA NEPTUNE 


(7) BEEF ALMOND INE WITH 


(60) OATMEAL WITH MILK 


(90) ON TOAST (2 SLICES) 


MACARONI 


(73) SUGAR 


(45) APPlfSAUCE 


(43) SPINACH 


(54) RAISINS 


(83) FRUITCAKE 


(50) CHEESE 


(31) SCRAMBLED EGGS 




(56) CRACKERS (6 CRACKERS) 


(91) TOAST (2 SLICES) 




(80) FILLED SUGAR WAFERS 


(75) JELLY 




(74) MARGARINE (1/2 TSP) 



riTEM IDENTIFICATION NUMBER 



260 



less than 10 to less than 20/g), Deviations were approvied hy the MDAC Medical 
Director. An additional 500 kilocalories of snacks wei« provi^d. Ihese con- 
sisted of nuts, raisins, and candy hars. 

For the frozen meals, Stouffer Poods, Cleveland, Ohio, was required to 
supply a minimum of 5 percent of the onhoard meals, preferably complete dinners 
amounting to approximately 800 kcal/meal. KASA microbiological standards were 
to be met. Meals were to arrive in frozen form and were to be packaged to 
require no more than 4,3 cu ft of storage. The latter requirement was imposed 
becaxise of the capacity of the onboard freezer. 

In addition, at the inquest of crewman, k pints of commercially available 
ice cream were placed onboard. 

TJ^e g^Lycerol (a sweetening agent having nutrient value) was obtained as an 
experimental food supplement from Dr. J. Shapira, KASA Ames Research Center. 
Interest in the glycerol as a food additive centered upon its acceptability as 
a sweetening agent, as well as on its physiological resolution after ingestion. 
A full description of this experiment is provided in paper no. 21 of this 
symposium. 

Data on food consumption vere provided daily tharoughout the mission via 
the TSCL data traxismission system available to onboard crewmen. Information 
thiis transmitted consisted of crewman identification, food items consumed, per- 
centages of foods not ingested, water vol-umes required for i^constitution, and 
relative acceptability ratings (l-9j 1 equals "poor," 9 equals ^'excellent"). 

Because of the late arrival of information on frozen foods, only the freeze- 
dried diet could be reported via the above-mentioned TSCL. Thus data on frozen 
food constmiption were obtained verbally from crewmen. 

Freeze-dehydrated foods were supplied in vacuum packages of a multilayer 
laminate which is xised by the Army to package similar foods for combat field 
distribution. The packages consisted of an inner layer of polyetl^lene, an 
intermediate layer of aluminum foil, another layer of polyethylene, and an outer 
layer of Itylar, the latter a flammable plastic. 

Within some packages of food Items was a dish con5)Osed of a waxy plastic 
(also flammable) which was to be used for reconstitution purposes. Utensils 
available to the crew were made of stainless steel. 

Frozen food was supplied in aluminum containers similar to TV diimer trays. 
These were covered with altraiinum foil. 

Ice cream was packaged in cylindrical paper contaii^rs. 

Because of the flammability of packaging materials in the food program, 
special precautions were taken in their onboard storage and disposal. Freeze- 
dried packages were grouped into f oxxr-man meal packages . OSiese were constrained 
with the use of fiber glass cable-tie cord and then overwrapped with three 
layers of hea-vy-duty aluminum foil. These were then stored in closed food 

261 



storage cabinets which had been examined and shielded to eliminate the danger 
of high voltage or other sources of ignition. 

Additional plastic food reconstitution dishes vere stored in specially 
provided, tightly covered alumintim containers which were also located away from 
ignition sources. 

Frozen meals were placed Inside the onhoard commercial freezer without 
additional preparation, as were the cartons of ice cream. 

Storage requirements for all onboard food provisions approximated 100 cu ft. 
Bulklness and nonuniform package sizing of freeze-dehydrated food contributed 
to using approximately ko cu ft more stot^e volume than originally allocated. 

All foods requiring elevated teraperatiires to eiahance palatability were 
heated in an onboard microwave oven. A Litton Indvistries Model 500 microwave 
oven was employed for food heatiiag. Daily measurements of microwave emissions 
were made throughout the test. After modification of the front door seals by 
the addition of adhesive-backed aluminum foil tape, readings revealed consistent 
levels of 0.1 mW/cm^ (average) with peak emissions tip to 0.2 m¥/cm2. At no 
time during the 90-day test did emissions exceed 0.2 mW/cm2. 



EESDIiTS 



Table 2 provides an indication of total food consvmiption for each crewman 
on day 90 of the mission and provides arithmetic means of dally caloric con- 
sumption for the crew over the entire 90-day duration.. It can be seen that 
intake averaged 2,89^ kcal/day/man . Differences in daily consumption among 



TASm 2 
FOOD CONSUMPTION 



Crevman 



Kilocalorles 
90th Day 



RLlocalories 
Mean 90 Days 



1 
2 

3 

h 



2,06t 

2,412 
if,04l 
3,561 



2,Tin 
2,822 
2,878 
3,137 



Grand Mean 2,89^ kilocalorles 



262 



crewmen are consistent with exercise regimens adjusted "by crewmen to their own 
individual requirements. This tahle reflects caloric values of all consumed 
foods excluding glycerol which was not a significant contrihutor to the total 
diet insofar as it was used for less than 10 percent of the mission duration 
and then only as a supplemental sweetener. Crew caloric intake is seen as 
inordinately high when conrpared with intake values from the previous 60-day 
test of a manned regenerative life support system wherein a mean daily consump- 
tion of under 2,000 kcal/man was reported. However, weight change data suggest 
that the 90-da'y values are consistent with the caloric requirements to meet 
actual crew work loads. 

Referring to table 5^ the overall acceptance of food on a rating scale 
extending from 1 through 9 was quite high — all food items on a group mean hasis 
received ratings of 6 and ahove. This is an unusxial finding for space simula- 
tions or operational missions and reflects increased attention given to the 
selection of food on the "basis of palatahility. 







TABTiK 5 










90-DAY FRKRZE-DRY K)OD ACCEPTMCE 






Categoiy 


1 


Crevman 
2 3 


k 


Mean 
Modal 
Preference 


Rank 
Order 


Soups 


7-50 


7.80 


7.20 


7.00 


7.38 


5 


Salads 


7.33 


6.33 


8.00 


8.66 


7.58 


k 


Entrees 


s.oii- 


8.21 


7.95 


8.07 


8.07 


1 


Dairy Products 


7.21 


7.iif 


7.28 


6.92 


7.1k 


7 


Vegetahles 


7.07 


6.69 


7.23 


7.53 


7.13 


8 


Fruits and Juices 


7-90 


J.kO 


8.36 


8.5^ 


8.05 


2 


Grain Products 


7.8if 


7.03 


6.k6 


5.69 


6.75 


9 


Desserts 


7.79 


6.08 


7.55 


7.26 


7.17 


6 


Sauces R.Tid Condiments 


8.80 


7.80 


7.80 


7.60 


8.00 


3 


Mean Modal 
Preferences 


7.72 


7.16 


7.5^ 


7.^7 






Rank Order 


1 


k 


2 


3 





263 



It shotild "be noted that althotigh group mean acceptance values are high, 
individual food items within the overall menu were occasionally ranked hy indi- 
vidual crewman at lower levels. Pood items falling in this_ category include 
such things as scrambled eggs and a gelatin dessert. Post-test crew remarks 
reflect the fact that scrambled eggs were rated low not "because their palatahil- 
ity left something to he desired, "but rather "because it was the only form of egg 
availa"ble throughout the mission. Hie gelatin dessert was rated poor by three 
of four crewmen "because of excessive sweetness. 

Table k summarizes the frozen food available to the onboard crewmen during 
the mission. Forty-eight meals were provided by Stouffer Foods, Cleveland, 
Ohio, and were stored onboard in a 4.5 cu ft freezer. These foods (substitutes 
for dinners) were provided to the crew with instructions t,o utilize them as they 
saw fit approximately once weekly throughout the mission. 

Crewmen chose to use these foods with a frequency of approximately once 
per week and otherwise employed them as a means of celebrating special occasions 
encountered during the mission. One such special occasion was a birthday cele- 
bration held for one of the onboard crewmen. 

Generally the frozen foods were well accepted by all crewmen but the crew 
indicated that they could have done without them had they been required to do 
so . Since they were available , they found them a welcome diversion from the 
freeze-dehydrated primary food menu. Negative renmrks reflected the feeling 
that, when compared with the primary diet, the frozen meals were overly rich. 
This combined with differences in strength of seasoning apparently resulted in 
some minor gastrointestinal difficulties. Interestingly, frozen meals were 
prepared utilizing the microwave oven even though the use of that piece of equip- 
ment with the frozen meals required frequent pulsing. Our crew did not report 
that this was an annoyance as have others. 

Microbiological Quality 

All freeze-dried and frozen food items were tested for microbiological 
quality by the vendors. The following criteria were specified and met by the 
vendor's products: 

A. Total aerobic covnt = less than 20,000/g 

B. Total coliform co^mt = less than lO/g 

C. Total fecal coliform cotmt = none/g 

D. Total Streptococcus count = less than 20/g 

E. Total coagulase positive Staphylococcus count = none/5g 

F. Total Salmonella coxuit = none/lOg 

Spoilage 

There was little if any spoilage of freeze-dried or frozen foods during the 
test. Several commercially packaged snack food items were foiind to be stale or 
otherwise unacceptable by the crew. Candy bars and cookies containing nut meats 

264 



TABUE 4 
FROZEN FOOD 

(8 OF EACH) 



DINNER WEIGHT ESTIMATED 

NO. CONSTITUENTS (OZ) KII.OCAt.ORIES 



1 SIRLOiN STEAK 8 6^ 

CREAMY POTATO BAKE 4 120 

ASPARAGUS SPEARS 3 20 

15 803 



POT ROAST OF BEEF 


3 


2^ 


BEEF GRAVY 


2 


SO 


DUCHKSe POTATOES 


3.5 


120 


GLAZED CARROTS 


3 


140 



11.5 575 



BEEF STEW 


10 


1,070 


SPICED PEACHES 


4,5 


90 


{2 HALVES) 







M.5 i.ieo 



BAKED CHICKEN BREAST 


5 


125 


CHICKEN GRAVY 


2 


90 


RICE 


3 


210 


CORN 


3 


60 



13 485 



LMABOiOPSm 


8 


630 


ESCALLOPCO MH>LES 


4 


3m 


GREEN BEANS 


3 


20 



15 915 



CHICKEN AND DUMPLINGS 10 S8S 

PEAS 3 60 



13 6«5 

265 



were found to have the shortest shelf life. IHie crew's discovery of a few fly 
larvae in the raisins provided an interesting diversion for hoth onboard and 
outside simulator personnel. Vacuum packaging, addition of antioxidants, and 
fresh delivery Immediately "before test start would alleviate this problem. 

Food Waste Management 

Reduction of food waste was accomplished primarily hy careful' selection, 
trimming, and apportioning of hoth freeze-dried and frozen food items hy the 
respective vendors. In addition, the crew was instructed in and fully accepted 
the inelegent but effective technique of licking their plastic food trays prior 
to spraying them with disinfectant. Leftover food waste exceeding several grams 
was scraped from the trays into a No. 2 can for canning following a heavy spray 
of the contents with disinfectant (8-hydroxyquinoline sulfate, 5 percent 
aqueous solution). 

Post-test microbiological assays of treated food waste revealed complete 
sterilization of the food trays, but only partial supression of growth in canned 
waste. Upon inspection of the can contents, it was evident that several cans 
had not been treated or had not been treated with sirCficient disinfectant to 
completely inactivate the contents. 

Sprayed food trays (plastic) were stowed in environmentally sealed aluminum 
boxes. Each box held approximately 500 trays. By coxmting the number of trays 
and obseiTing the box fill dates, an average use rate of 2 trays /man/meal was 
calciilated. 

lEhis figure is lower than pretest estimates and the crew confirmed saving 
of trays by multiple-use techniques such as tising the same tray for preparation 
of more than one item or using one tray for preparing a double portion. The 
■use rate of stowed trays would have been even lower had more care been taken 
during handling of several freeze-dried food items already packaged in trays . 
These trays had become cracked during the bundling and wrapping operations 
before stocking of the simulator. 



COHGLUSIONS 



Freeze-dehydrated food is an acceptable diet for long- duration missions. 

It may be desirable to defray the monotony of a single diet with foods 
prepared and stored utilizing other techniques. 

Reheati3ig of reconstituted freeze-dehydrated food apparently served to 
increase the acceptability of this diet. The microwave oven was simple to use 
and quite effective in perfonning this function. 

Mien employing combined diets, it may be necessary to adjxist seasoning and 
"richness" to achieve greater acceptability. 

266 



Greater attention must be giyen to the selection of containers and food 
packaging materials from the dual standpoints of flammability and storage 
density. 

Negative reactions to food provisions are a phenomenon which can he elimi- 
nated through the combined efforts of food selection oriented tovard palatahil- 
ity, the provision and utilization of a means whereby foods can he heated to 
acceptable serving temperatures, and provision of an acceptable variety in 
available diets. 



267 



USE OF GLYCEROL AS A DIET SUPPLEMENT DURING A HIWETr-DAY MANNED TEST 

By Jacob Shapira 
NASA. Ames Research Center 



SUMMARY- 



The crewmen during a ninety-day manned, test ingested a glycerol solution 
mixed with various other food materials during two different five-day periods. 
The glycerol diet supplement was judged to the "better than average" and did 
not lead to an elevation in serum free glycerol. An erratic and inconsistent 
idse in urine-free glycerol, as determined by an enzymatic method, was obseirved. 
As expected, there was no nausea or ill effect observed during the use of free 
glycerol as a food adjunct. 

INTRODUCTION 



Glycerol dates from the earliest days of organic chemistry when its isola- 
tion from fat as an individual compound was first reported by Scheele in 1779 
(ref. 1). Its name derives from the Greek "glutos," meaning sweet, since it 
had a sweetness almost as intense as sugar. Later, its structure was shown to 
he 

CHp-OH 

I 

CH-OH 

I 

CH2-OH 

which in most aspects is quite similar to the structure of sugars. 

Along with heing found in food as a conrponent of fat, free glycerol is 
present in small amounts in feimented materials such as beer, wine, and hread. 
Further, it is now commonly added In relatively small amounts to foods in which 
it is not normally present to confer desirable physical properties. It is also 
utilized hecause of its desirable solvent properties in the foormulation of a 
wide variety of pharmaceutical preparations and is useful in the campoTondlng of 
food flavorings. Glycerol is "generally recognized as safe" hy the U.S. Food 
and Drug Administration. 

It was not until 1902 that Cremer demonstrated that glycerol was processed 
by the body to produce glucose when he reported that diabetics excreted addi- 
tional sugar when fed glycerol (ref. 2), This gluconeogenic attribute of glyc- 
erol was later confirmed by Catron and Lewis in 1929 with the demonstration that 
ingestion of glycerol by fasting rats led to an increase in liver glycogen 
(ref. 3)» Since then, extensive studies have been conducted which repeatedly 
show that the most important pathway of glycerol metaholism involves its rapid 
conversion in the body to glucose. 

269 



The current confidence regarding the lew oral toxicity of pure glycerol 
has not always existed. It is possible that early preparations contained by- 
products which resulted in reports of nausea, vomiting, and injurious effects. 
It remained for Johnson, Carlson, and Johnson in 1933 to disprove effectively 
injiurious effects in animals and man when significant amounts of glycerol were 
consumed (ref. k). They reported that after extensive preliminary testing in 
rats and dogs consuming almost one-half of their diet as glycerol, they then 
fed 110 g of glycerol per day to ten men and four women for a period of fifty 
days. This amount of glycerol could provide ahout k'J^ kcal which would amount 
to almost 20^ of the daily calorie requirement of the subjects . There were no 
significant changes in the "blood and urine analyses performed nor was there a 
change in the basal metabolic rate. ITo evidence was observed of diarrhea, 
abnoimal intestinal activity, sleeplessness, or excitement - effects which have 
been previously reported by others. 

Based upon the report of Johnson, Carlson, and Johnson (ref. h), and other 
subsequent reports of the innocuous effect of the oral ingestion of glycerol by 
man, it was decided to investigate the suitability of glycerol as a potential 
physicochemlcally regenerated food during long-duration space mj-ssions. Two 
other aspects of the problem, aside from its nutritive qualities, had to be 
investigated: the feasibility of its manufacture frcaa waste during the mission 
and its psychological acceptability. 

The problem of manufacture has been pursued to the point where currently it 
can be stated that the feasibility of the following synthetic sequence has been 
demonstrated: (l) reaction of respiratory carbon dioxide with hydrogen to yield 
methane; (2) oxidation of methane to formaldehyde; (5) self- condensation of 
formaldehyde to produce foimose sugars; and (k) hydrogenolysis of formose sugars 
to give glycerol plus other low-molecular- weight polyols. Separation of pure 
glycerol from the mixture remains to be accomplished. 

The problem of acceptability of glycerol under simulated aerospace condi- 
tions is the subject of this report. The crewmen of the ninety-day test agreed 
that they would consmae k-O g per day of food grade glycerol in four 10-g doses 
during two different five-day periods. They woxild also report their evaluation 
of different flavorings and methods of ingestion. Concurrently, analyses of 
blood and urine samples would be conducted to determine the possible physiologi- 
cal effects of this supplement to their diet. 

MTEEIALS MD METHODS 



The glycerol used was Reagent Grade per the specifications of the American 
Chemical Society. It was diluted with distilled water to give a solution con- 
taining 1 g glycerol per ml of final volume. Lemon and lime flavors were recon- 
stituted juices obtained from a local supermarket. The coniposltlon of other 
foodstuffs such as "Kool-Aid," dehydrated coffee and tea, used by the crew in 
combination with the glycerol are reported in paper no. 20 of this compilation. 

0?he glycerol solution was provided in a 1- liter plastic automatic dispenser 
set to deliver 10 ml of the solution each time. The crew was Instructed to mix 

270 



this quantity of solution with a single flavor or mlxtxire of flavors, dilute 
"With at least five volumes of water or "beverage, and consutae. The Sweetness of 
10 ml of the solution was equivalent to ahout 1 teaspoon of sucrose. The crew 
was also instructed to allow at least 2 hours "between ingestions, which could he 
before, during, after, or between meals. They were to record the total volume 
of liquid consumed and their subjective evaluation of the mixture using the fol- 
lowing five-point s cale : 

1 = like very much 

2 = better than average 
5 = acceptable 

k = might try again 

5 = will never try again 

This five-point scale satisfied the requirements of this escpeilment and is 
similax to a standard hedonic scale used in food preference studies. 

The blood samples used were portions of the weekly collections described 
in paper no. k^ of this compilation. As a normal part of the serum lipid study 
performed on the samples by HMEI, values for serum-^free glycerol were deter- 
Biined and are reported herein. 

Analysis of weekly urine san^iles for free glycerol was kindly performed by 
D. ifyexs of MDAC using a variation of the Boehrlnger Mannheim Corp, protocol 
for the enzymatic analysis of serum glycerol utilizing the following reactions; 

Glycerol + ATP :^ Glycerol- 1-phosphate + ADP 

ADP + PEP :;^ ATP + Pyruvate 

Pyruvate + KADH + ff*" ^^ Lactate + HAD+ 

The reduction in absorbancy of the solution at ^66 nm due to the loss of JHADH 
was equated with the glycerol pi^sent. 

The accuracy of the method for urine samples and the recovery of added 
glycerol is indicated by the following excei^pt f ram. a letter by S. KLotzsh, 
Chief Chemist, Boehrlnger Ifennheim Corp. 

"Following the methodology for serum, our laboratory assayed three differ- 
ent urine samples (0.5 ml per test) and also the same specimens with the addi- 
tion of 1 fflg and 2 mg^ of glycearol: 



271 



Eecovered Glycerol 



Sample 


1 


2 


3 


Without addition 


0.21 


0.28 


O.l^I^ 


Plus 10 |jLg glycerol/ml. 


1.25 


1.28 


1.57 


Plus 20 (ig glycerol/ml 


2.20 


2.19 


2.1^8 


percent recovery 


103, 100 


100, s6 


95, 102 



The urine was filtered prior to use to exclude particle interferences in .the 
measurement of optical density. A difference of time or rate in comparison to 
serum samples was not observed. " 

KESULTS 



Glycerol as a food additive was quite acceptable to the crewmen. During 
the first period in which they had access to this material, there was consider- 
able e3q)erimentation with va3n.ous flavorings. In addition to its formulation 
as beverages, on a nimber of occasions it was added to cereal and fruits with 
good reports. As can be seen from table I, the recorded evaluations indicated 
that it was considered to be "better than ayerage." 

During the second period of ingestion, the acceptability declined somewhat 
to approximately "average." The degree of experimentation with flavors -vms 
very much reduced and one of the crewmen was satisfied merely to dilute the 
glycerol with water throughout this phase. None of the crewmen in either of 
the test periods fovmd any formulation to be -unacceptable. General comments at 
the end of the test indicated that the crewmen thought the taste of glycerol 
was detectably different from sucrose. Its convenience as a sweetener was 
thought to be desirable. 

Analysis of blood samples drawn immediately after the period of glycerol 
consumption indicated a nonsignificant rise (P > 0.1, t test) in the level of 
free glycerol when compared with the levels observed one week prior to or after 
the test (table H) . Even when all base-line values were pooled for statistical 
analysis, the Increase was not significant. 

The restilts obtained with urine saarples are more difficult to interpret. 
There is a highly significant rise in the amount of glycerol excreted (table II). 
However, there is a wide difference in the levels of excretion by the different 
crewmen. This may be due to individual physiological variations but other fac- 
tors may also have had an effect. For instance, diiring the last few days of 
each test period, there were deviations from the protocol with regard to the 
time between consumptions and the amount consumed at a given time. Also, 
during the second test period, because of unanticipated losses of glycerol 
solution, not all subjects held to the regime until the end of the test; in 

272 



fact, crewman 1 terminated glycerol Ingestion after only three days tecaiise of 
the shiortage. Further, some crewmen consiaaed "doable doses" or single doses in 
rapid succession. It can "be predicted that this woxild result in elevated 
excretion of glycerol. 

DISCUSSION 

As was e2q)ected, it was found that even with the stress of the ninety-day 
test, acceptability of glycerol was high. Since it is known that glycerol is 
very rapidly metaholized by the body to primarily glucose and to a lesser degree 
directly to carbon dioxide, it is not siorprising that no elevation in serum- 
free glycerol was observed several hours after the last ingestion. In theory, 
the amount consumed could give rise to a transitory threefold increase in the 
seriM level of glycerol, but this would be observed only if absorption was very 
rapid and measurements were performed within minutes after consumption. 

It is thought that the rate of excretion of glycerol into the urine is 
directly proportional to the serum concentration of free glycerol. This may 
help to explain the difference observed between the ampunts excreted before 
and after the first test period and the corresponding values obtained during " 
the second test period. The mean volum;e of urine during the collection day of 
the first test period was 11^1-0 ± 265 ml whereas it was 19^0 ± 205 ml during the 
second period. The difference is significant (P < O.O5, t test). The same 
sitxiation obtained with regard to the excretion of glycerol. During the base- 
line periods of the first glycerol ingestion, total excretion of glycerol was 
2.2^4- ± 0.25 mg per day while during the second period, it was k-.k-3 ± O.k^ mg 
per day. Again, the increase was highly significant (P < 0.01, t test). Thus, 
the normal excretion rate of glycerol seems to parallel the total volume of 
urine, a situation which would be expected if glycerol excretion were a passive 
process. 

The passive nature of glycerol excretion does not explain the extent of the 
elevation observed during test. The wide variations in glycerol excretion com- 
plicate the situation. However, the fact that the relative amounts excreted by 
each crewman during the two different test periods was essentially in the same 
order would suggest individual physiological differences. Further studies are 
planned. In any case, the average excretion of glycerol during test represented 
less than 0.1^ of the Ingested amount and can be considered negligible. 

Because of shortage of glycerol, crewman 1 terminated his consumption of 
glycerol about 10 hours before beginning the collection of urine. As seen from 
table II, his urinary excretion had returned to normal values, which indicates 
a very short retention time for excess glycerol in the body. This is consistent 
with known rates of glycerol metabolism as determined by studies involving 
radioactive glycerol and measurement of the excretion of radioactive metabolites 
such as carbon dioxide (ref. 5)« 



275 



KEFERENCES 

1. As cited lay Dalton, N. N. and Kern, J. C, in "Glycerol," Edited lay Miner, 

C. S. and Dalton, N. H. , American Chemical Society Monograph Series, 
Reinhold Publishing Co. , New York, 1955. 

2. Cremer, M. , Munch, med. ¥och., ^2, Shk (l9Ce). 

5, Catron, L. F. , and Lewis, H. B. , J. Biol. Chem. , 84, 555 (l929). 

k-, Johnson, Y. , Carlson, A. J,, and Johnson, A., .Amer. J. Physiol,, IO5 , 517 
(1955). 

5. Young, D, R, , Fe1,.l1gra, R. , Shapira, J,, Adachi, R. R. , and Skrettingland, K. , 
J. Applied Physiol. , 2^, T^ (196?). 



271+ 



TABLE I.- ACCEPTABILITY- OF GLYCEROL AS A FOOD ADDITIVE 



Crewman 


6/25/70 to 6/50/70 


8/20/70 to 8/25/70 


W-umber of 
consunrptions 


Eating* 


Ninn'ber of 
consumptions 


Rating* 


1 
2 

5 

k 


20 
20 

Ik 
20 


2.1 ± 0.2 

2.2 ± 0.1 
1.5 ± 0.2 


12 

Ik 

15 

16 


2.9 ± 0.1 
3.0 ± 0.1 
2.9 ±0.1 
2.9 ± 0.1 



%ean ± ^M. See text for description of five-point rating scale. 



**, 



Cre-wman failed to give numerical rating. 



TAELE II.- SERIM-FKEE AHD UEIKE-FKEE GErCEROL 



^\^ewiian 
Date ^"\,^ 


Serum-free glycerol 


, mg^ 


Urine- 


free glycerol, mg/24 hr 


1 


2 


5 


k 


1 


2 


3 


k 


6/25 


0.7 


0.8 


0.9 


0.6 


2.7 


1.9 


1.7 


3.7 


6/50 (test) 


0.6 


0.7 


1.2 


0.8 


I8.lt 


59.0 


106.0 


2.8 


7/7 


0.7 


0.7 


0.9 


1.0 


1.7 


2.5 


2.8 


1.6 


8/18 


1.2 


0.9 


0.9 


1.2 


k.k 


5.0 


5.9 


5.0 


8/25 (TEST) 


*1.2 


1.1 


9.1 


k.2 


*5.5 


30.7 


65.7 


5.8 


9/1 


1.1 


0.7 


1.5 


0.9 


5.5 


2.9 


5.6 


3.1 



Crewman tezmlnated consuurption o£ glycerol about 10 hours before 
collection of xirine. 



275 



MASS BALANCE DATA 
By J. K. Jackson, L. G. Barr, and J. F. Harkee 
McDonnell Douglas Astronautics Company 

SUMMARY 



The overall nnass balance for the SSS in the 90-day test may be evaluated 
by considering the potable water recovery unit, the wash water recovery unit, 
the atmosphere supply, and the oxygen recovery units. Over the 90-day 
period, urine production averaged 13.09 lb /day and respiration and perspira- 
tion losses by the crew, 11. 70 lb /day. The cabin latent load was increased 
by wash water evaporation of 560. 3 lb and excess humidity generated by the 
solid amine unit of 1, 075. 1 lb, so that a total of 2, 688. 7 lb (or 29. 87 lb /day) 
of humidity condensate was removed from the cabin. Potable water produc- 
tion, certified for crew consumption, was 2, 356. 7 lb (26. 19 lb /day), of which 
2, 044. 6 lb (22. 72 lb /day) was actually consumed by the crew. Of this potable 
water production, 1, 308. 6 lb was produced by the VD-VF unit during its days 
of operation and 1, 048. 1 lb by the wick evaporator or fronn humidity conden- 
sate. The humidity condensate was also used to supply the solid amine unit 
(1, 148.0 lb), for makeup to the VD-VF unit (643.8 lb) to support its feed 
requirements, for makeup to the wash water unit (512. 9 lb), and other miscel- 
laneous uses. 

The wash water recovery unit produced 10,447. 6 lb (116.08 lb /day) of 
water at the dispenser, of which 560.3 lb was lost by evaporation, as has 
been mentioned. 

The atmospheric gas supply furnished 862. lb of oxygen and 278. 9 lb of 
nitrogen to the SSS. Part of the oxygen (137. 4 lb) and all of the nitrogen went 
into losses, leakage, and atmospheric samples, leaving a balance of 724.6 lb 
(8. 05 lb/day) of metabolic oxygen consumption by the crew. The oxygen was 
primarily furnished by water electrolysis, including 22.4 lb by the Allis— 
Chalmers unit, 566. lb by the Lockheed unit, and 258. 3 lb by the commer- 
cial electrolyzer serving as a backup. The balance of 15.3 lb was supplied 
by high-pressure storage. Water for the Allis— Chalnaers and Lockheed units 
was supplied by the Sabatier reactor (332.0 lb) or from an onboard storage 
reservoir (330. lb). A total of 81. lb of hydrogen was supplied by electrol- 
ysis for the Sabatier reactor, with a balance of 24. 9 lb being vented during 
periods of inope ration of the Sabatier. 

The COo concentrators removed a total of 752. lb (8. 36 lb /day) of CO2 
from the cabin. A total of 636. 9 lb was processed through the Sabatier 
reactor along with the 81.0 lb of hydrogen. The balance was vented 
overboard. 




277 



INTRODUCTION 



The system mass balance has been determined from performance data on 
potable water recovery, wash water recovery, the water electrolysis units, 
two-gas control, Sabatier reactor, and CO2 concentrators, and from input/ 
output data on the crewmen. These life support subsystems have been pre- 
viously described. Determination of the mass balances involved detailed 
consideration of the operating modes of the various units as they varied during 
the test. The overall mass balance presents valuable information on the 
average input and output parameters of the crewmen. Subsystem and unit 
performance can best be evaluated by examining in detail various segments of 
the mission during which representive combinations of operating modes 
occurred. Because of the accuracy of instrumentation and the many locations 
in which temporary storage occurred, these segments must be long enough to 
obtain accurate ayerages. 

SYSTEM DESCRIPTION 



Mass balance data were determined by a review of data from many 
sources. Flowmeters and totalizers were installed in most major gas and 
water transfer lines. Quantity raeasurements in potable and wash water tanks 
were made continuously by strain gage load cells supporting the tanks. 
Quantities in other tanks Were measured before and after the test. The two- 
gas control used pulse counters to total the amount of gas supplied by the 
flight-type electrolysis units, the backup (Stuart) electrolysis unit, and high- 
pressure oxygen and nitrogen facilities. Records were kept, particularly in 
the latter portion of the test, of water supplied to the Lockheed electrolysis 
unit, which provided an improved calibration of the two-gas oxygen pulse 
counter. Some variation in the water flowmeter calibrations was encountered 
in the potable water system. Fortunately, very detailed and accurate records 
were kept of water transfers by the inside crew. Much of the water system 
mass balance depended on these records. 

TEST RESULTS 

Discussion of mass balance test data will include consideration of the 
potable water recovery, the wash water recovery, the atmosphere supply, 
and the atmosphere recovery units. From these data and other records, the 
crew input/output requirements can be determined. Each of these areas will 
be discussed in detail. 

Potable Water Recovery 

The potable water recovery unit represented an integration of the VD-VF 
radioisotope heated unit and the wick evaporator for recovery of water from 

278 



urine. Water was also recovered from humidity condensate. Final purifica- 
tion of water w^as accomplished by multifiltration and storage was in four 
heated use tanks. When possible, the water produced by the VD-VF unit was 
pumped directly to a use tank; when potability standards were not met directly, 
this water was also processed by multifiltration. The usual requirement for 
reprocessing was a positive microbial sam.ple or excessive ammonium ion 
concentration in the VD-VF condensate. These variations have already been 
discussed in detail in paper number 5« 

Figure 1 shows the overall potable water balance for the 90-day period. 
During this time 1, 178. 5 lb of urine were produced, averaging 13.09 lb /day. 
The respiration and perspiration losses of the crew were determined by sub- 
traction of recorded data on water sources from total water production, and 
were found tb be 1, 053. 3 lb (11. 70 lb /day). Contributing to the total load on 
the humidity control separator condenser were also 680 lb of urine vapors 
from the wick evaporator, 560. 3 lb of wash water evaporation, and 1, 075. 1 lb 
of water vapor from the exhaust of the solid amine unit. The total humidity 
condensate was 3, 356.4 lb (37.29 lb /day) of which 3, 172.4 lb was removed by 
the Lockheed hydrophilic /hydrophobic condenser- separator, 76.0 lb by the 
silica gel desorbate condenser, and 108. lb by the condensation that occurred 
in the thermal control unit. The Lockheed separator actually separated 
2, 647. lb from the air stream, allowing the balance of 525. 4 lb to pass 
through; this was separated downstream by gravitational forces. The sepa- 
ration efficiency was therefore 83. 5 percent, which was undoubtedly consid- 
erably reduced by the unexpectedly high condensation rate which was several 
times the design value. 

Unprocessed humidity condensate was supplied to a number of units which 
did not require water meeting potability standards. These included makeup 
water to the solid amiine boiler (1, 148 lb), makeup for the evaporation in the 
wash water unit (512. 9 lb), and makeup to the VD-VF unit (643. 8 lb). The 
latter was required because the feed rate to the VD-VF boiler must be held 
constant to accommodate the constant heat input rate of the radioisotope 
heaters. Since it was necessary occasionally to reprocess urine in the wick 
evaporator that had already been diluted for feed to the VD-VF unit, the 700 lb 
of feed to the wick evaporator included some humidity condensate as well as 
urine. 

Where product water from the VD-VF unit met potability standards, it 
was pumped directly to the heated use tanks. This included 460.0 lb. When 
these standards were not met, 848. 6 lb of VD-VF water was processed by 
multifiltration. Of the total 2, 356. 7 lb (26. 19 lb /day) of water certified for 
potability during the test, a net increase of 81. 9 lb occurred in the four use 
tanks and 2, 044. 6 lb (22. 72 lb /day) were consumed by the crew. Of the 
balance, 49.8 lb were passed out of the chamber for analysis, 81.4 lb were 
returned to the wash water unit, 43. 4 lb were added to the VD-VF feed 
(possibly being reprocessed after onboard sampling) and 55.6 lb were trans- 
ferred overboard as contaminated waste. 

Of the water transferred to the solid amine unit (1, 148. lb) and not 
returned to the cabin as humidity (1, 075. 1 lb), a total of 55 lb were 

2T9 



transferred to the wash water unit, 12.2 lb were removed with the CO2 pro- 
duced, and 5.7 lb were transferred overboard. 

To show variations in water circulation during various operating modes, 
some segments of the total period were examined in more- detail. Figure 2 
presents one of these segments, for the 8-day period, test days 5 through 12. 
During this period the solid amine and VD-VF units were operating and no 
wick evaporator operation occurred. In deriving this chart, average valties 
were used for urine production, crew latent loss, wash water evaporation, 
urinal flush water, VD-VF vent losses, and boiler residuals. Other values 
represent recorded data during this period. It will be noted that VD-VF 
production averaged 20. 58 lb /day, and none of this product was multifiltered. 
The total humidity condensate averaged 30.47 lb /day, of which 12. 70 lb /day 
resulted from the solid amine unit. Diluent water to the VD-VF feed was 
58.48 lb or 7.31 lb /day most of which was provided from the humidity 
condensate. 

Figure 3 shows the 8 -day period from test day 46 through 53, when the 
wick evaporator and solid amine units w^ere operating and no VD-VF operation 
occurred. Again, 90-day average values were used for urine production, 
wash water evaporation, urinal flush water, and wick evaporation residual 
solids. Actual data were used for crew consumption (23.35 lb /day) and 
average metabolic water production was used to determine crew latent loss 
of 12.33 lb /day. All other data represent measured values. During this 
period, the solid amine unit contribution to cabin humidity was 8,48 lb /day. 
The wick evaporator w^as processing urine which was previously diluted for 
VD-VF feed, averaging 21. 93 lb /day. The total humidity condensation rate 
was 48.8 3 lb /day, which was one of the peak periods during the test. An 
average of 26. 09 lb /day w^as certified for crew consumption. 

Figure 4 shows data for the final 10 days of the test. On day 81 the 
VD-VF and the solid amine units were both shut down for the balance of the 
test. This period represents operation on the molecular sieve CC^ con- 
centrator and the wick evaporator. At the beginning of this period approxi- 
mately 65. 75 lb of diluted urine was available which was processed in the 
wick evaporator as well as the urine produced. No further dilution of the 
urine occurred from humidity condensate. Also, the crew was actively pre- 
paring for the end of the test, and a number of extra cycles of the washer/ 
dryer were performed, increasing the wash water evaporation loss to 8. 67 
lb/day. Even so, the total humidity condensate was down to 20.84 lb /day 
because of the shutdown of the solid araine unit. The evaporation rate of the 
wick evaporator was 22. lb /day, producing a total condensation of 42. 84 
lb /day. Of this, the net inventory in the tw^o potable holding tanks was in- 
creased by 81 lb and the potable use tanks by 44 lb, averaging an increase of 
12.5 lb /day. 

Wash Water Recovery 

The mass balance for the wash water recovery unit is shown on figure 5. 
During the 90-day period, a total of 10,447. 6 lb (116. 08 lb /day) was dispensed 

280 



by the unit. Of this 560. 3 lb (about 5 percent) was lost by evaporation. Much 
of this was probably from the clothes dryer and sponge bathing. Makeup water 
included 797.8 lb from various sources to compensate for evaporation losses 
as well as 207.4 lb used for urinal flush water and 101.4 lb of other losses. 
The net change in inventory in the holding and use tanks was a loss of 75 lb. 
About 500 lb of w^ash water was reprocessed after changes in multifiltration 
coluncms to remove accumulated contaminants. 



Atmospheric Gas Supply 

Figure 6 shows the overall mass balance for the atmospheric gas supply. 
Oxygen for this supply and hydrogen for the Sabatier reactor were nornnally 
generated by water electrolysis. Initially this was done by a flight-type unit 
built by AUis -Chalmers and installed inside the SSS. However, as explained 
in paper number l^J-, this unit soon had operational problems and was respon- 
sible for generation of only 22.4 lb of oxygen and 2.8 lb of hydrogen. Most of 
the balance of the test depended upon the Lockheed unit which was installed 
outside the SSS and generated 566.02 lb of oxygen and 70.75 lb of hydrogen. 
These units were supplied with water produced by the Sabatier reactor (332 lb) 
or from a storage reservoir inside the chamber (330 lb). The hydrogen 
generated was normally used by the Sabatier reactor, although it was shut- 
down for periods of time during which it was necessary to vent 15. 6 lb. 

When neither flight-type water electrolysis unit was able to meet cabin 
requirements, supplementary oxygen and hydrogen were produced by the 
commercial Stuart electrolysis unit. This amounted to 258. 3 lb of oxygen 
and 23. 00 lb of hydrogen. Since the Stuart unit was manually controlled at a 
fixed electrolysis rate, the excess gas generated was vented, and measure- 
ments were not made of the amount of water supplied to the unit. 

In addition to the 846. 7 lb of oxygen generated by electrolysis, 15. 3 lb 
were supplied from the high-pressure storage unit. This was done once on 
day 6 when the oxygen setpoint of the two-gas control was increased by 10 
torr, and approximately 4 lb of oxygen were added manually to compensate. 
Other usages of gaseous oxygen occurred during several short periods when 
none of the electrolysis units were functioning. 

Nitrogen was supplied from high-pressure gaseous storage and con- 
trolled by the two -gas control. Total nitrogen usage was determined from 
the pulse counter totalizer on this unit. This amounted to 278. 9 lb, or 3. 10 
lb /day. Of this input, 2.30 lb of N2 and 1. 10 lb of O2 were removed frona the 
SSS for atmospheric analysis. The balance of the nitrogen is indicative of 
losses and leakage. Average analysis of the CO- output of the molecular sieve 
and solid amine units indicates a total of 20. 4 lb of N2 and 10. lb of Oo were 
removed with this gas. Other losses may have occurred by undetecteci leaks 
in the VD-VF vent, the commode sealing valve, the commode fecal sampler, 
the dry waste can vent to annulus, and other sources. Data are not available 
to define these values. Previous experience with the SSS indicates that basic 
chamber leakage is normally very low. In any event the total of unaccounted 
losses and leakage is 256.2 lb (2.85 lb /day) of nitrogen and 126.3 lb (1.40 

281 



lb /day) of oxygen. The remaining 724.6 lb of the oxygen t8. 05 lb /day) is 
accounted for by crew metabolic consumption. 

Atmosphere Recovery 

The miass balance for atmosphere recovery is shown on figure 7 for the 
90-day period. In this system, CC^ is removed from the cabin either by the 
solid amine or the molecular sieve unit. Purity of title CO~ rennoved was 
determined by periodic analysis of samples taken outside the chamber. 
Average values of these analyses were used to determine the nitrogen and 
oxygen removal with tiie CO2. Also, the effluent CO2 from^ the solid amine 
unit contained excess water. After the test, 5. 5 IV of water were remioved 
from the CO2 accumulator. Additional water vapor was present to establish 
an average dewpoint of the GP2 of about 75*'F. This resulted in remioval of 
about 12. 2 lb of water from the SSS during the 69. 5 days of operation. The 
molecular sieve unit provided CO2 with a dewpoint of about -50 "F, and there- 
fore removed very little water fromi the cabin although there may have been 
somie water entrapped in the beds. 

The Sabatier reactor was normally operated with all the produced CO2 
being processed through it. However, low CO2 feed rates were used during a 
period of intermittent operation before the catalyst change, and venting of CO2 
occurred during periods when it was not operating. During one period when 
catalyst poisoning was suspected, 28.3 lb of bottled CC^ was furnished to the 
reactor in an attempt to regain catalyst activity and COg removed from the 
cabin was vented. 

The CO2 feed to the Sabatier reactor necessarily included 02» No, and 
H2O as impurities. Analysis indicated the hydrogen feed to be essentially 
pure. The esdaaust gas was passed through a water baihi, in which the increase 
in water content was noted to determine the loss of water in the exhaust vent, 
and measured by wet test meter. Average of periodic analyses determined the 
vent gas composition, which confirmed the presence of nitrogen and CC^. 
Normally the oxygen content was very low, indicating that it had reacted with 
hydrogen in the reactor to produce product water. Unreacted hydrogen w^as 
vented, including some during short periods of reactor operation with excess 
hydrogen to produce catalyst reduction. The Sabatier reactor operated for a 
total of 80 days, producing 332. lb of water for an average rate of 4. 10 lb/ 
day. Peak rates were somewhat higher. 

Crew Input /Output 

The input/output of the four crewm.en is shown on figure 8. As indicated, 
the input included averages of 8. 05 lb /day of oxygen, 22. 7 lb /day of water, 
and 5. 4 lb /day of food. Most of this food (approximately 90 percent) was 
freeze dehydrated. The crewmen showed a net weight increase of 2.25 lb. 



282 



Output of flie crewmen included 8.47 lb /day of CO^. The derived 
respiratory quotient was therefore 0. 76. Crew respiration and perspiration 
averaged 11. 70 lb /day. The urine output of 1, 178. 5 lb was found to include 
49.8 lb of solids and 1, 128. 7 lb of reclaimable water, for an average of 12. 54 
lb/day. The reclaimable water in urine, respiration and perspiration was 
therefore 24.24 lb /day; 1. 54 lb/day or l38. 6 lb m.ore thaji the potable water 
consumption. Water was collected in the commode freeze traps (52.2 lb) and 
26. 6 lb of dried fecal solids in the commode. Total fecal production was 
therefore 78.8 lb or 0.93 lb /day. 



283 



z 
o 

s 

Z3 
M 

Z 

o 

ui 
oc 



UJ 

o 



< 

< 



liJ 

I- 

> 

UJ 



UJ 

en 

< 

o 

CL 






o 
c 
< 
o 
oa 

K 
UJ 

> 
O 

M 

MiA lij zc ~ 

*- 3 g 5 

"" o 

ed 



uM2 
3^? 



0> 

lU 



'^S 



u 



2 5 

UI GC T- 

>l- w 



CM " 

t 



15 



o 

EC 

< 

UI e 
Q ^ 



K 
UI 

!i 

s 

X 
M 

< 

t- 06 



K 

J 

Si 

=> o 



Si5 268 ?s ?^9 

t t t t 



ID 



3 JO 



CO oc 

O UI 

3 » b m 



SB 



UtUJ 

> 



UI 

'I 



M 
UI 

-I 



OS 
_l« 



K I- 

UJ X 

» UI 

I * 
i i 

g § 

a. ' £ 
3 Q 

^ S O 

< JJ X «9 

2 u» <j rj 



1111 



I ° 

UI O 
(9 U 
< -i 

I ^ 

fe s 
a E 

I- Q 

s < 

CD 
K 



OC OC 

t oz^ 
1 zz£d 

88^1: 



I; 

o 

OC 

u. 

OC 

g 

< 

OC 

yj 
O 



Ui 

o 

-I 

UJ 

(9 



CO 

S 
O 

flC 






3) 
•1-1 

1^ 



281^ 



O 



OQ 



c/> 


> 


w 


< 


< 


Q 


S 


00 


S 


CM 


UJ 


X 


1- 


C9 


> 


3 
O 


ifi 


X 




1- 


tr 


in 


I4J 


> 


h- 


< 




o 



(^ 



Ul 
CD 



O 

a. 




O 

u 



•o ^ 






285 



Ill 

Q 

3 



< 



< 
o 

tn I- 
*!^ 

ill ut 

3 I- 
ttk 

< 

O 







4 


k 


4 


4 


S4 


















y- 








§ 




tc 


5 








MM 




t 


!D 








s 


^Mk 


CO 


O 










IS 


I 


tu 




' 


t '=t 


3E 

UJ 
flC 


Ml 

* 05 


I 3 


z 
oc 




8 


1 




i 


k 














Ui 


)- 










Z 


C9 






M 




s 


z 






UI 




< 


o 






! 


S2S 


u 


1 


1 








^% 


IB 


p5 




f 






^^^^_ 


§5 
















" 3l 








gl 


S 








^ 1- 




KtC 




tc ' 


, 




ills* 




1 

tc 
m 
a 






xSo^tu 




*^ 








£ 
u. 
ut 

CC 


• 






g f 


'^ 


Mb 


H «» 










< 
CC 


^1 


I 






^ 


,- 2 




S' 








i 






K < 


^ Ui 


-i 








3 


1 


S s 




wis 

- ■ ■ 


V ^ 


ill 




is 3 


1^ 


1 

5 






1 


^1 


S 


1 


i 


' a 

r* 




I i 


L 






ft? 
















Ui 












1 












&« 










w 








i 


n^x^ 111 


5 




i 


^S s 


^ 


z 












lU 




1 
1 

( 


u 

£ 




11 


III 


1511 


S 









i-fc 

gzS 
• • • 



•1-1 

fa 



286 



O 



C/> o 

< ^ 

X 



Z 
O 

z 

3 
M 

z 
o 
u 

s 

LU 

oc 
u 






i 


i 


t 1 















cc 








< 








§ 


CC 







QC 


f- 






Ul 


< 


Ul 




s 


H 


-1 




M 


=s 


a. 





UJ 


cc§ 


^ 
^ 


d 


^ 


4.63 

TOU 
ACC 



Ul 

Z 



s 



Ul UJ 

< 

O 



4 4 4 




tc 


H 




UJ 


X 




H 


a 




i 


Ul 




X 

i 




f? 


CL 




Z 


Ul 

-1 
a. 
S 


3 

Ul 


1.49 
HOLD 


^ 


d S 


s*< 



o 
oc 
o 

!5 

oc 

I- 
z 

Ul 

^^ 

So 

08 

2> 

f~ Ul 

l3 



Z 

o 

cc 

Ul 

Q. 

o 

I- 
z 

3 
UJ 



< 

O 




•r-i 



4 S 



M 

Ul 

-J 

a. 
S 

Si 



o 



Ul 

z 

E 

3 





^ 


k i 




















Ul 










^ 










i 


H 
Z 

UJ 

S 

S 

oc 


30 

RINAL FLUSH 
fATER 




OM POTABLE 
NK 


54 

EFRIGERATOR 
EFROST 


p>S2 


oc 


R£^l 




Q. 


Ir-- 3SI 


r-- OCOI 



So 

U. M 
OC UJ 

UJ Q 

>-l 

O Ul 

o< 
wgF9 

Ul "- _l 
O UJ < 

<!8I 



in 



5 

z 

« 



287 



oe 



z 

CO 

3 



< 
Z 

e 

3 



8 



3 
S 
3 
U 

o 

< 

lU 

3 



(A 

Ui 

-I 

au 
S 



s ss 



M 



uj a 

I- c 

M UI 

< > ro 

3 O ei 



s 

UI 



w 



Ui 

O 



< 

m 

< 



< 
Z 

< 





t 


1 


[ t 


_t 


t 




. 


' « 








A i 


1 






i 


J- 


»" 


^ 






*. 


UI Z ^ 


1— 








a> 


£9 < ? 








£ 




3 H ^ 


3 

UI 






M 




i 


k 


O 
O 






E O 










i 


li 










^ 


\ 
i 


r 










L 




«? 












H 




e 

UI 

1- 


a. 

3 






f- 


i 

• 


^ 
^ 


|g 










H 












_l 












* 














t ■ 


1 t 


t 

UI 


t 

-1 


1 


t 


i 


O UI 




-1 M 


K 


t- 


o 


o 


g 


S 2 
111 -1 

Ii ta ! 


3 


Ul 

O 

UI 

Z 


if 

UI Z 

5 85 


5 

K K 
U. U. 






s 
















UI 
















5^-* 


^ 














9 5** 


^ 










^ 


r 














s 















u 

•1-1 



s;;:; 



288 



m 



a 



< 
m 

< 



< 

O 

0^ 
UJ 

X 
0. 
CO 

o 



COCM *" 
UJ — —I 







M 



a. 

IS 

COCM 



rm 



< 
< 

UJ 

_i 
Q 

If 

CO r-' 
lU — 

O M 

—J «— 



UJ 



So 



CO 



289 



M 

> 
-I 

o 

»- 

u 

UJ 

-I 

UJ 

Oo 



DCS 



UJ 

o 



< 



tr 



< 


^^ 








s 

^ 


"5 


i 


z 


o" 


S5 


H|o 


*R 


N 




|si 






s 




>" 


(M 


«— 


o 



n CM 




1 



UJ 

O 
O 



?tK 



C^t- 00 in 



^m 














N .. 


.. O 


o 








8 i'S'i' 


o 










/ 


Ly 










/ 


ir 










I 


UJ 






576.3 - 

(8.30) 

15.9 


» 


1 

CM 


175.7 
(8.55) 

2.2^ 


X 










,, 




CL 






o ^ 


Jp" 


H, 


O PJ PM 


m 






u z 


o 


z 


z o 


O 






























S 




M 






oc 

< 


2 




5 


o 

3 


AMINE 

UNIT 

69.5 DAY 






^UJ 


zQ 






^ 






UJ _ 
-iCfl 


3«« 

8 








i 






i 


^ 






> i 


I 










H 












O 












IN AIR 

MHUM 

TROL 






















eaOZ 












<a:o 














UUL 


u 












<0 

u 



290 



< 
I- 
< 

Q 



I- 



O 

o 



< 
a. 

CO 



r^ o < 

CO 



to 
o 

o 

CO 



oo 



I—I CD 



or: 



1^ CO 

. Q 

OO — 

^. O 



Of 



NO 

• 
NO 
CVJ 



lr\ 



• In; 



CO 

UJ 

Q 



CM 

CM 
lA 



CO 

o:: 

UJ 



NO 

in 

« 

CO 



< 

CO 

Q 

OOO g 



S 



vO 

Sir: 




^ 


'^ 


jS*^'^ 


UJ 






tf 






O 






UJ 






O 






< 




IK ^ 


UJ 


CVJ 

O 


22S 



00 

•iH 



o 



00 <=> 


2 











CO 

UJ 


CO 






—1 






< 



CM 



NO 



CM "-J 

Siicvr 






^ 








UJ 








0£. 

















2 








< 








:S 















■^ 


QC 






UJ 


_^ 
















UJ 


u- 






—1 


g 


5 


QQ 

—X 




u. 


Q 


— i 




CO 

UJ 

< 


OQ 
1 

>< 
>< 


i 

1— 

X 




> 


X 



291 



THERMAL BALANCE DATA 

By J, K. Jackson and G. E. Allen 
McDonnell Douglas Astronautics Company 

SUMMARY 



Thermal conditioning of the Space Station Simulator (SSS) during the 90- 
day test was done by a cooling loop circulating Coolanol 35 at 32 to 40°F. 
Process heating fluid was also provided by a circulating loop using electrically 
heated Coolanol 35. This loop supplied the carbon dioxide concentrators: the 
solid amine unit at about 240°F and the molecular sieve unit at 320°F. Total 
heat removed from, the chamber varied from 22, 846 Btu/hr (6, 695 kW) to 
29, 514 Btu/hr (8. 650 kW), depending on operating mode of the life support 
units. This total does not include thermal control requirements for water 
electrolysis, because operating time on the AUis- Chalmers unit was too short 
to reach equilibrium and the Lockheed unit was installed outside the SSS and 
separately cooled. 

INTRODUCTION 



The design of the thermal control subsystem is presented in 'paper number 7^ 
To review, coolant is provided frona external dual redundant refrigeration 
units that simulate a space radiator. The coolant, which is Coolanol 35, is 
supplied at 32 to 40°F at about 14 gpm. Coolant is supplied to a number of the 
life support units within the chamber to remove the heat generated and is also 
used for atmospheric cooling in the thermal conditioning unit to pick up all 
heat rejected to the atmosphere. The SSS is insulated to reduce heat transfer, 
and is operated at a temperature very close to the outside environment. It is 
estimated that heat transfer between the SSS and outside was less than 1, 000 
Btu/hr under any operating mode. 

Process heating fluid, which is also Coolanol 35, is furnished to the 
chamber from an external, electrically heated reservoir. This fluid was used 
either by the solid amine or the molecular sieve CO2 concentrator. Original 
plans for the SSS also included a Coolanol heated oven, but this unit was elimi- 
nated before the test because of possible nnaterial inconapatibility. As the 
molecular sieve and solid amine systems were not required to operate simul- 
taneously, the proper circuit temperature was achieved by setting the heater 
therraostat at the reservoir. This was approxim.ately 240°F (115°C) for the 
solid amine unit and 320°F (160°C) for the molecular sieve unit. 




295 



The thermal balance includes all equipment normally operating inside the 
SSS. However, the AUis- Chalmers water electrolysis unit performed nor- 
mally only during the first two days of the test. Adequate data are not avail- 
able to determine its performance. The backup water electrolysis unit, built 
by Lockheed Aircraft Corporation, was installed outside the SSS due to lack of 
available internal space. It was provided with a separate coolant source. No 
thermal performance data were obtained on this unit, 

SYSTEM DESCRIPTION 



Equipment which must be considered in the thermal balance is listed in 
table 1, This shows the major heat producing and removal equipment. 
Although some condensation did occur in thermal conditioning unit, this 
amounted to less than 3 percent of the maximum total latent load. Condensa- 
tion also occurred in the solid amine unit, although this was rarely enough to 
remove all the water vapor introduced in the steam de sorption of the beds. 
Condensation in the silica gel bed desorbing air stream of the molecular sieve 
assisted in reducing the cabin humidity. Condensation that occurred in the 
Sabatier reactor exhaust and VD-VF vent gas did not influence the cabin latent 
load since these exhaust products were vented to overboard vacuum, 

SYSTEM PERFORMANCE 



The thermal balance was subject to considerable changes from day to day 
as the operating modes of the various life support units jwere changed. Chief 
among these variations were the following: 

A. When the wick evaporator was processing urine, an electrical air pre- 
heater was used, adding about 1, 020 Btu/hr (300 watts) to the heat input 
to the unit. 

B. When the VD-VF unit was not operating, heat generation by the Pu-238 
radioisotope capsules was removed in a storage chamber cooled by the 
coolant fluid loop. 

C. Large changes in thermal inputs occurred, depending on use of the solid 
amine or molecular sieve units for CO2 removal. 

D. Changes in latent load from the washer and dryer resulted from variations 
in the laundry operations. 

In order to describe system operations with these variations included, 
data is presented in figures 1 through 4 representing unit operating modes for 
four typical days of the mission. These are as follows: 

Figure 1, Day 23: Molecular sieve and VD-VF operating, solid amine 
not operating, wick evaporator preheater not operating. 



Figure 2, Day 50: Solid amine unit and wick evaporator preheater oper- 
ating; molecular sieve and VD-VF not operating. 

Figure 3, Day 58: Solid amine unit and VD-VF operating. 

Figure 4, Day 83: Molecular sieve unit and wick evaporator operating. 

Although these represent typical days, data presented for each unit gener- 
ally represent averages over m,uch longer periods of time. The crew sensible 
and latent loads are averages for the entire mission, and were derived from 
caloric values of food intake, net weight change, and respiration/perspiration 
values from the water recovery mass balance data. Values for the molecular 
sieve and solid amine units represent averages over significant periods of 
apparently normal operations. 



295 



u 



UJ 

o 

I 

< 
m 



t—i 
1 1 1 


UJ 


s 

Q^ 


LLj 


^Hi 


UJ 


LU 


Q^ 


X 


hi 


O 1- 




0. 

0. 


z 




— » 






a> 


o 
yj 




UJ 





-I o 



—1 

5 

O 


CO 

UJ 
CO 


X X 


3Z 


5 


X • t X • 


o 


QQ 
CO 

s 

CO 


XXX X X 


o 

o 
o 
on 
a. 


1— 

5 


X • * X 


UJ 

DC 


—1 

< 
o 

1— 
o 

UJ 


X X X X X X X 




1— 

UJ 
UJ 


C02 REMOVAL 

SOLID AMINE UNIT 

MOLECULAR SIEVE UNIT 
SABATIERrrOXIN 
POTABLE WATER RECOVERY 

VD-VF 

AIREVAPORATOR/HUMIDITY CONTROL 
LIGHTING AND RECREATION 
CREWMEN 
MISCELLANEOUS, INCLUDING: 

WASH AND POTABLf WATER STORAGE 

REFRIGERATOR AND FREEZER 

HOT PROCESS FLUID LINE LOSS 

EXPER IMENTS 

MISCELLANEOUS UNITS 
THERMAL CONDITIONING UNIT 



UJ 

u. 
O 



CO 



CO 
CO 

y 

CO 

< 



CO > 

a: I- 

UJ 

UJ 

QO 
"I 

> o 
o o 



oo Qi ^ 
^ UJ O 

> X < 

> I— o 
z >- — ' 
O m I- 

I 1 2 

O < t= 
=3 > < 
Q O -^ 

P S !=i 

Ci; m < 
Q_ a: ^ 

UJ UJ ^ 

x: 3: ^ 



§^i 



CO 
UJ 



296 



CO 

> 

< 
o 

tr 
o 



o 

a. 

> 

LU 

o 

1 

m 

< 



^ 



JC9Z 
2< 

m— ^ 






ococ 

I ^i' 

Z ujO 

sill 

Q SOC 



lU 
UJ 

-i 

< 

s 

Q 
M Z 

UJ < 

Q T 

d| 

z * 



O UJ 
CO 

8| 

«>"■< 
ui 



z 
S 



UJ 



i s 

< wco 

UJUJ<_|5 

OnuJqS 
= ujiSoc 

OC X UJ 



o 

s 

H 
5 ^~ E 3 

pizw 

2l*Duj 
_iO caU- 

cco: ou! 

-lO 



ujm 

OCUl 



< 
IT 

UJ 



IS 



M 
UJ 
M 

" UJ >3UJ 2 ^ 

7 SSt-H^ UJ -'o 
gS<GQ.^OCUJ< 

'"3uJ;,<<b:o 

ZlS>OL<iJ 



UJ 



^ 



o 

coOZ 
MZ< 

wboo 
Q. xsm 






U 



M 
Ul 



!§ 



zz 



(9 



:=z 



lag 

-ICCUJ 




o 



z < 

-JO o 

ujZ^ujS 
I O Z _i M. 
I- U 3 UJ rC 






S(0 






UJ 
QC 
UJ 

X 

85 

o 

s 






o 

00 



en 




CM 



UJZ 
ocs 



UJ 

a. 

< r- 



U 



00 



c^z 

UJ ^ 

1?P 



S 



^o<— 

ujuioh 
SmoCuj cm 



J 



Pi 



297 



o 

ID 

> 
< 

Op 

^ 5 

UJ 
O 

< 




EC 

li ^ 

OS N 

iiiii 

U O S DC QC 



o 

5 
_i 
u. 

oc 
ua 

IL. 



c 



$A 




UJ 



< 



Ui 
OQ 

-I • • 

u 

z 



UJ 



M 



CO 

Q 

< 

O 

CO _l 

Ql!i>3 !yz< 

U<S<5 ^GCIU 
uJZxS >flu< 




SI 



cc 
o 






9 



Q 
ZZco 

<ot 
a 



lU 



z<- 



(9 



us 



-lOCU 



^< -I 

'•' Ml 

>3UJN 



z < 

JO o 

luzEuje 
xpZ-|(M. 









s 



B'l 



!5. 



8 




— <uj Z_i„ 
< oc oc 3uJf4 



UJ 

So 




•r-l 



GC 
lU 

lib 







_UIZ 
CO0C3 



298 



00 

in 

> 
< 
a 

o z 

U. z 



-I 

£8qs 



cc 

OS 
S = E 

zwwE 



^ Q 

y jiiosis 



tl 






OS 



NO 

acui-3 
2o£ 

S<M 

oo^ 
Stch-wm 

UJO^X 
CCZ-ltU 



M 



o 

z 
< 

< 



M 

o 



III • 



< 



UJ 

-1 
< 

s 

O «« 
<UJS 

<5uJ 
5 _■ 

• '— 

CO £ 
.. CC ») 
O lu lu 
Z S 3 
lU S J 
O 3 < 
UJ Z> 



CC 
Ul 



•!3< < 

0CC"O 

8sS::i 

uu 



M 

Ul 4_ 

9 tu £ 

lyz^co 

3 ui-'q 
-> GCUJ < 

5SSS 



tii 




O) 



CC 

u 



CO 
UJ 






!$ 



<OI- 
^OCUI 



ui< 
z> 



< 



So3ui cm' 



CM 



a 



< 



- z 
lb '^ 

ujz!=ui5 
XOZ_|(H. 
t-U3uJr>« 



18^ 



s — 




li 



CM 



CC 
UJ 

z 

I 

S' 

!5 






s 



o 

00 



Q 



s 



'I ^ 

o<> < 

< «U K 

>£> H 

uJOpi_bo 

i=<uj Z-jo 
<CCCC3UJ "• 



fa 

CM 



z 

=_l 

X 
cco 

0& 

Ul_| 

JMkJHb 



CO 
UJ 

a. 

O?: 
Z*. 



CO 



00 



lit 







UJui 

S cacc 



299 



CO 
00 

>■ 
< 

Q 
OS 

o 

< 
g 

Q. 



o 



CD 

< 

UJ 



< 



^ 



^ 



o 



oco: 

DC HP 
Ul — 



s 



^ si 

to t* 

•- &s 

Z ujO 

2""tOQ.u- 

uja.<< 
O Sec 



5 u.. 



DC 5q 



_ Z 

O <JIM 

GCOCH — UJ 
UJui<-JS 

(C I lU 

• • • 

c 
o 



a: 

l3 

lu O 
-J DC 
fflH 

<Z 

to 

CL > 



o 

-. s 
cc t- 

lU oc 

DCUfXcoS- 

ogiiw 

ZjqDUI 

<<2e2!i: 
!iioc^5$ 



■■^ nn Lb en # « en ^to «^ 



0<11J 

zS- 



«3o(QSoc 
<iuJ2Po 

■^ III "^ 



UJM 
DCUJ 



M 

UJi 



DC<lMHb 
:iu>3UJZ*H W 



CM 



lU 
DC 

u 



UJ 



* S-J 



!? 



Q 
ZZ 

Z<5 

lag 

.JDCLU 




O 






i-i 






DC 
lU 

X 

85 

o 

s 

5 




S 



m 
O 



s 




•iH 
1^ 



00 



^1- 

flCg 



S M DC lU (M* 






300 



ELECTRICAL. POWER DISTRIBUTION AND USAGE 

By J. K, Jackson and N. A. Jones 

McDonnell Douglas Astronautics Company 

SUMMARY 

The electrical power subsystem, for the 90-day test included 60 Hz, 115 Vaci 
1 phase; 400 Hz, 120/208 Vac, 3 phases; and 28 Vdc. Power usage was recorded 
by watt-hour meters on each 60-Hz circuit, watt meters on each 400-Hz cir- 
cuit, and ammeters and voltmeters on the dc circuits. Automatic recording of 
pow^er data was provided by six power sensors on groups of the ac circuits and 
a shunt in the dc circuits. These signals were recorded on the low- speed data 
system (LSDS). 

Electrical energy usage was 8, 169 kWh on the 60-Hz circuits, 5, 885 kWh 
on the 400-Hz circuits, and 2, 257 kWh. on the dc circuits. The total energy was 
16, 012 kWh, for an average power consumption of 7, 425 watts. Power and 
energy requirements of each unit are presented. 

INTRODUCTION 

The power distribution system for the Space Station Simulator (SSS) was 
designed to meet all industrial code requirements. As a result, a large 
ntimber of circuits were provided and many of these were very lightly loaded. 
Further requirements were established during the safety reviews which 
included insurance that each circmt wire gage was adequate for the circuit 
breaker protection provided and that each using element was fused to prevent 
destructive currents. An example of the latter was the provision of individual 
fuses on electric motors that were selected to protect against locked rotor 
current values. 

Instrumentation was provided to establish average and instantaneous power 
readings. Insofar as possible, this instrumentation was intended to show the 
power requirement for each unit, but constraints on circuit arrangement and 
the numbers of available instruments prevented full achievement of this 
objective. 

In designing and operating the life support system, efficient design from a 
power reqmrement standpoint was a secondary objective. In many cases, 
inefficient components were selected for economic reasons. Similarly, no 
effort was made to schedtile operation of intermittent equipment to influence 
the occurrence of power -load peaks. 



501 



SUBSYSTEM DESCRIPTION 

The electrical hardware incorporated into the SSS was designed to use one 
or more of the following power forms; 115 Vac, 60 Hz, single phase; 
120/208 Vac, 400 Hz, three phase; and 28 Vdc. 

Twenty 115-Vac, 60-Hz circuits were utilized with 20-amp circuit protection 
in each circuit. Table 1 shows these circuit allocations. One 120/208- Vac, 
400-Hz circuit was employed with a maximum circuit capacity of 50 anaps with 
individual breakers on each unit. Table 1 indicates circuit allocations for this 
power. Two 28- Vdc circuits of 60 amips each were utilized to supply 28- Vdc 
power to the SSS/LSS. An additional onboard 28- Vdc power distribution panel 
was incorporated for more efficient distribution of tiie 28-Vdc power. A third 
28- Vdc power circuit provided power for the test control area. 

Backup power supplies were connected in parallel with the primary 28-Vdc 
and the 400-Hz motor generator to allow fast manual switchover if necessitated 
by loss of the primary supply or need for preventive maintenance. 

An emergency backup 28-Vdc supply was incorporated into the overall 
electrical power systena to automatically activate should the facility 115-Vac, 
60-Hz power fail. The emergency power supply consisted of a battery pack 
which, when activated, provided power to the emergency power bus for 
emergency onboard lighting and control of all safety- oriented chamber control 
functions. The emergency battery pack was maintained at fxill voltage with a 
trickle charger when not on line. 

The electrical power distribution system incorporated relay isolation of 
all electrical power entering the chamber with the exception of intercom, 
television camera power and emergency lighting circuits which were classified 
as essential for safety of the crew. The electrical isolation circuits were 
integrated into the automatic abort sequence. The power system block diagram 
is shown on figure 1. Seven power sensors, also shown in figure 1, were used 
for measuring power on groups of circuits as shown on table 1 and figure 1. 
These sensors provided amillivolt signal proportional to actxial power for the 
ac circuits. A shunt was used in the dc circuit, With power being computed 
using the nominal 28-V terminal voltage. All millivolt signals were recorded 
by the low- speed data system. 

SUBSYSTEM PERFORMANCE 

The SSS power subsystem experienced two major facility 115-Vac, 60-Hz 
power failures, the longest lasting approximately 20 sec. The major pow^er 
events are shown in table 2. The power failure produced no problems with the 
onboard or facility support equipment, but required restarting the a:ffected 
systenn.s. The emergency backup 28-Vdc activated properly and provided the 
required SSS lighting and chamber control power. The backup 400-Hz motor 
generator was used on days 66 and 67 to facilitate preventive maintenance on 
the primary miotor generator drive belt. 



302 



The average power consumed during the 90-day run is diagrammed in 
figure 2. The detailed subsystem power consumption and total power for the 
90- day run are itemized in tables 3 and 4. 

Power consumption for the run ■was derived from commercial watt-hour 
meters as shown in figure 1 identified by WHR prefix. Additional power 
instrunnentation was incorporated into the SSS power lines to allow real-time 
recording of instantaneous power on all lines entering the chamber. The real- 
time power instrumentation is shown in figure 1 with identification prefix 
of WIR. 

Three power profiles were made during the run on days 38, 67, and 79. 
Samples were taken and recorded on the low- speed data systein every 4 minutes 
for each of the three 24- hour periods. Figures 3 through 8 show the resulting 
power profile for the ac power circuits on the 67th test day. 

Power provided to the Lockheed electrolysis unit which was located Out- 
side the SSS was not included in the SSS power instrumentation system. During 
the run, the following power was provided the Lockheed electrolysis unit while 
it was on line and supplying gas to the SSS: 

300 MA 120/208 Vac, 3 phase, 400 Hz (3 sec on, 15 min off) 

2. 5 Amp 115 Vac, 1 phase, 60 Hz for controls and the oxygen 

compressor 
1, 300 Watts DC on high mode operation, 1, 349. 1 hr 

445 Watts DC on low mode operation, 140. 1 hr 



503 



Table 1 
SSS EQUIPMENT POWER CIRCUITS 



Meas. 
No. 



Circuit 



WIR-DZ 


A2 


115 Vac 




60 Hz 






A4 




A6 




A8 


WIR-D3 


Al 


115 Vac 




60 Hz 


A3 



AS 



A7 



Refrigerator, clothes washer, waste management, elec- 
tric ove * Sabatier/ Toxin, crew^ life support, dfew point 
pump. 

Airlock Controls, crew area lights. 
Clothes dryer. 

Air samplers (2), critical task testor, pass thru port con- 
trols, conductivity meter, T.V. monitor, solid amine air 
compressor. 

Bed, lights (2), T.V. monitor, vision testor, incubator, 

timer, deep freezer, radiation monitor. 

Bed lights (2), portable nuclei counter, equipment area 

lights (4) 

Dew point pump, bio-medical ergometer, VD-VF, mass 

spec, flight weight, two-gas pneumatics, base line 2-Gas. 

Microwave Oven 

Wash tank #8 

Potable tank #3 

Potable tank #5, water circulation pump. 

Solid amine 

Sink pump. 

Wash tank #7, waste overboard pump. 
Potable tank #1, wick evaporator air heater. 
Potable tank #6, metering water pump. 

Potable tank #2 

Thermal control, nuclei counter air pump. 
Potable tank #4, urine liquid level control 
CO2 concentrator 

Alii s- Chalmers electrolysis, baseline and flight weight, 
two- gas Sabatier/ Toxin, CO2 concentrator, crew life 
support, potable water dispensor, solid amine, waste 
management, wash water control, potable Water control. 

Lithium hydroxide*, CO2 concentrator, wick evaporator, 
commode, thermal control. 



WIR-D4 


C2 


115 Vac 


C4 


60 Hz 


C6 




C8 


WIR-D6 


CI 


lis Vac 


C3 


60 Hz 


C5 




C7 


WIR-D7 


D2 


115 Vac 


D4 


60 Hz 


Dl 




D2 


WIR-Dl 


B 


28 Vdc 




WIR-D5 


F 


120/20B 




Vac 




3 phase* 




400 Hz 





* Not used during 90-Day Test. 



30li- 



Table 2 
SIGNIFICANT POWER SYSTEM EVENTS 



Test 

Day Time Event 



10 12:06 DC Power surge on all consoles, problem traced to a 

momentary short created by onboard crewman working 
on AUis- Chalmers electrolysis unit. Onboard DC breaker 
for unit tripped, reset breaker ^yith no problem. 

28 09:50 SSS 115-Vac. 60-Hz circuit A5 (20 amp) circuit breaker 

tripped due to short in VD-VF control wiring. Corrected 
short and reset breaker and performed a restart on mass 
spectrometer. 

40 02:00 Facilities 115-Vac, 60-Hz power momentarily failed, lost 

coolanol system, solid amine and 400-Hz motor generator, 
perform restart on affected systems. 

45 08:30 SSS 115-Vac 60-Hz circuit A5 (20 amp) circuit breaker tripped 

due to short in VD-VF liquid level switch, corrected mial- 
function, reset breaker and performed a restart on mass 
spectrometer. 

57 06:30 Facilities 115-Vac, 60-Hz power failure occurred for approxi- 

mately 20 seconds, all onboard and SSS support systems went 
OFF, emiergency SSS 28 -Vdc battery power automatically 
came on to provide SSS lighting, maintained communication 
system via communication backup battery supply. Performed 
normal restart on all affected systems with no problem. 

66 08:50 Switched to backup 400-Hz motor generator to perform. 

preventitive maintenance on drive belt of primary motor 
generator. 

68 08:00 Switched back to primary 400-Hz motor generator. 



305 






Pi 
o 

H 

<; 

CO 

O 

I— I 

El 

<2 

E-i-^ 
CO --' 

W - 
O o 
<; nS 

s> 

W in 
O 

^o 

W 
(4 

a 

w 

O 



!h 




<U 




^ 


■s;- 


O 


w 


Ph ^< 


(U 


Eh 


bo 


<3 




^ 


fl) 




> 




< 





I— I 

bO 
(a 



S 



fl 
o 
ft 

a 

o 
U 



CT^ 


ra 


r^ 


r- 


■— 1 


LD 


M 


CO 


00 


• 


• 


« 


• 


• 


• 


• 


• 


• 


O 


in 


o 


-* 


M 


r- 


o 


sO 


M 


^ 


(M 


o 


o^ 


vO 


00 


1— 1 


ID 


ro 


fva 


r^ 


o 


CO 


t^ 


rj 




t^ 





IT) 



(M fVI 



^4* 
ID 



vO 



PJ 



a 






p 






"a 


0} 


■u 

nJ 


■u 
CO 




a; 
1— 1 


CO 


CQ 


■u 


U3 


Rj 


O 




^ 


ft 



00 

in 



fM 





!^ 








(D 








■i-> 








nJ 












ft 




0} 




ft 


■u 


+> « 






ni 


fli ft 




tiO 


<u 


ig 




c! 


K to 


to 


Uj to 


^f 


■g^ 


1 




03 3 


nJ -i^, 


3 


o •« 


Hft 


H.;^ 


ft 


•H O 



O nO 
00 o^ 
1—1 rvj 



U U >U 



00 



^1 
ft 

§ 

O 

o 

(U 
0) 

:S 

u 
o 



fSJ 1—1 

ro CO 



a 

o 

•H 

cq 



bO 

bo u 









10 










•H 




r-1 






to 




O 


0) 




!>^ 




f^ 


> 




•-4 


a 


4-1 


4) 




o 


• iH 


a 


•1-1 




u 


X 


o 


CO ^ 


(0 


4J 


o 


o 


;h to 


a-^ 


(0 m 


EH 


1-1 


nJ >s 




rt l^' 


' 


ni 


ri d 


H nJ 


u 


a 


3q 


<:p 


^Q 




u 


-2: 






«3 
A 


^^ 


o — ■ 

CO 


^^ 


CO 



00 

•H 
ft 

(U 
(U 

<0 
CO 

o 



o 



o 
u 

o 

u 

CO 

o 



o 

u 

o 
o 

o 

ID 

cd 
o 



o 

4J 

a 

0) 



a 

u 
d) 

•Li 

CI 
•1-1 

I-l 
i-1 
c« 

a 






u 

CO 
CO 



o 

CO 

en 

0) 

r 

o 
u 



• o 

CO <*i 
CO 



CO 



u 



CD U 



(U 






(« 



<u 
a 
o 

.3 a 

" "ill 



9) 



s,a 



p nj 

^ « 

^ cd 

4J 

<Si 

o 
o 



u 
o 

<: jft 
* < 

CO 

W 
Eh 
O 



506 



Eh 



o 

< 

I— I 

O 

n 
Eh 

< 
Eh 

W 
O 

<: 



o 

> 

00 

P 

tsi 

o 
o 



O 

CO 

M 

w 
w 

l-H 
P 

a 

H 

w 
o 



Q 
D 

U 

I— I 
>^ 

:^ 
p 

03 



^4 
ni <! 



3 

MS 

(0 

d 



o 
ft 

a 

o 
U 



•a 
p 



0) 
ID 

m 



0) 

u 

o 
w 

M 

I 



00 

in 
o 

sO 



o 

u 

o 

U 

U '3 

^ a 

o s 

m6 



O 

U 
O 
ft 

> 

W 
o 



00 - 
O N 

o o 

<V1 o 

.-1 ^ 



ro 



nO 


00 


IT) 


o 


vO 


IT) 


ro 


CO 


^a 



fNJ 



in 

CO 



o 



in 



o 



fvj" 



00 



vO 



* 



o 
o 

in 

00 
00 

in 



CO 

u u 

o o 

1—1 .—I 

cq m 



(U 

> 



H 
O 


•iH 


O 


^H "ra" 


r-4 


n! >> 


(d 


•-J aJ 


a 


So 


^^ 


^ o 


EH 


o- 

s 



bO 
c! 
■1-1 

ft 

(U 

en 
O 



<! 
H 

o 

Eh 



<V3 

in 



in 

ON 

1—1 



O 



O 

fO 



00 

sO 

o 



00 

00 

fO 



ON 
fM 



<1 

nO 1-1 r^ 

• • • 

CJN vO 1— I 

CO ^H o 

^H 00 CO 



in 
pa 



CQ 








u 








(U 








a 






^■^ 


4^ 






w 


rt 


03 


tJ 


S 


^ 


>N 


<u 


rt 


O 


rt 


<u 


P 


1 

0] 


P 






•H 
r-l 

1—1 


;* 


o 
O 




<; 




J 



10 

r-l 
O 

O 
<U 

r-l 

w 

u 

(U 

-u 





u 




<a 




rQ 








ci 


EQ 


,s^ 




U 


P 


(U 




tJ 


fn 


•H 


lU 


(d 


r^ 


rt 



o 

> 

00 



<: 

H 

o 

Eh 






00 



a.2 

O ,Q 

fuEH 

O 3 

H O 



in^ 

^ o 

,-1 nO 



00 
I— I 

o 



CQ 
1— I 

<: 

Eh 

o 

Eh 



o 

M 
O 

y 
o 



3 N 



a. 2 

<U .H 

d m 

a «» 

(1) t» 

h (U 
•I-l 

a< o 
jj o 

. M O 







.a fl <" 5 



0) 



to tS 

a 5p-« 



0) 

b JJ 
m <u 0) o o. 

<i m h^i js o 



CO 

W 
O 



307 




a. 
Z 
< 

s 



CL 

s 
< 



^x 



'< 



n 



a 



CO 

OS. 
UJ 



M 

III 



u. 



o 

38 



U 

z 
111 
a 

Ul^ 

il 



ll'JsTsJB sj oT 3[ s" ut s) st at at „ 



■( 



w 







1 



it 



1 



I 



I 



,« 



t 



■(^^■^ 



1 



I 

2 



I 



1 



I. 



ill 



U 

K 



T_ 



m 
a 







EC (0 








is 




a: + 




'^ 




S§ 






iH 


^1 


<U 


U 


SS 


•i-i 


lii 


[H 



< 

Ul 
K 



Ul 

u. •- B 



508 



iZ 



< 

1^ 



< 

ui 

z 

o 











Nl 

:<" 

O 

< 








C3 


I— 












- oo 


I 

AMINE UN 

E 
1 


< 
> 

1— 1 




> 

1—4 




RATION 
ATION 


O 
O 

> 

g3 




/SOLID 
/ONLINI 










MERS OPE 
ERS OPER 






"N 

1;;;^ 


X 








X < 
CO T 




- K 


J7) 










10DULE AL 
)DULE ALL 




o 


MOLECUL 
ON LINE 




h 






^THREE N 
^TWOMC 




M 

s 




v. '"^ 






^- 






pi 






^~k 
















s 















«— * 



< 
o 

1X4 



1/S ^ €*% CM •— » 

(SUVM) NOIidWnSNOO a3M0d 39Vd3AV 



309 



POWER LOAD PROFILE 

CIRCUIT WIR-D2 



DAY 67 



4,000 
3,600 
3,200 
2,800 
















n 


1 1 

REFRIGERATOR 




1 — 1 1 

FTP CONTROLS 


■^ 




- 
















SABATIER/TOXIN TV MONITOR 

CREW LIFE SUPPORT SOLID AMINE COMPRESSION 

DEW POINT PUMP CRITICAL TASK TESTER 

S?^yjt2^,f„b'^»"J^ ELECTRONIC OVEN 

CLOTHES DRYER* 

CLOTHES WASHER' *NOT ON LINE 






























H 


























5 2,400 


































ui 2,000 


































1,600 




J 
































! 


1,200 
































..,!.... 


800 




















u_ 


















_J 








J 








Ll_ 


400 














































3.00 6.00 

TIME ZERO - 00 00 00 ON 8/18/70 



9.00 12.00 15.00 

ELAPSED TIME (HOURS) 



18X10 



21.00 24.00 



Figure 3 



POWER LOAD PROFILE ■■ DAY 67 

CIRCUIT WIR-D3 



4.000 
3,600 
3,200 

2,800 

I 

g 2,400 

i 2,000 
S 

1,600 

1,200 



800 



31 



m 



BED LIGHTS 

TV MONITOR 

INCUBATOR 

TIMER 

DEEP FREEZER 

RADIATION MONITOR 

PORTABLE NUCLEI 

COUNTER 

EQUIPMENT AREA LIGHTS 



az 



t: 



t: 



DEW POINT PUMP 

BIOMEDICAL 

ER60METER 

MASS SPECTROMETER 

2 GAS SYSTEM 

VD-VF CONTROLS 

MICROWAVE OVEN 




3.00 &00 

TIME ZERO -00 00 00 ON 8/18/70 



9.00 12.00 15.00 

ELAPSED TIME (HOURS) 



21.00 



24.00 



Figure 4 



510 



POWER LOAD PROFILE - DAY 67 

CIRCUIT WIR-D4 




3^ 6.00 

TIME ZERO -00 00 00 ON 8/18/70 



9.00 12.00 15.00 

ELAPSED TIME (HOUBS) 



21.00 



24.00 



Figure 5 



POWER LOAD PROFILE • DAY 67 

CIRCUIT WIR-DS 



4.000 

3.600 

3;m)0 



2^00 



LITHIUM HYDROXIDE BLOWER* 

COj CONCENTRATOR BLOWER* 

WICK EVAPORATOR BLOWER 

COMMODE 

THERMAL CONTROL BLOWERS 

•NOT ON LINE 

(400 HZ LOADS) 



^^^%^ ,fif^ 



2.400 



I 



2.000 



1.800 



1.200 



800 



400 



3.00 6.00 

TIME ZERO -00 00 00 ON 8/18/70 



9.00 12.00 1S.00 

ELAPSED TIME (HOURS) 



16.00 21.00 24.00 



Figure 6 



311 



POWER PROFILE ■ DAY 67 

CIRCUIT WIRO® 




TIME ZERO 



3.00 6.00 

■ 00 00 00 ON 8/18/70 



9.00 12.00 15.00 

ELAPSED TIME (HOURS) 



21.00 



24.00 



Figure 7 



POWER LOAD PROFILE - DAY 67 

CIRCUIT WIRD7 



4,000 
3,600 
3,200 
2,800 



POTABLE TANK 2 
THERMAL CONTROL 
(60 HZ ONLY) 
NUCLEI COUNTER 
AIR PUMP 



u 2,400 
£ 2,000 



1,600 

1,200 

800 

400 



tf 



J 



U 



J. 



3.00 6.00 

TIME ZERO - 00 00 00 ON 8/18/70 



9ja0 12.00 15.00 

ELAPSED TIME (HOURS) 



21.00 



24.(H> 



Figure 8 



512 



MAINTENANCE AND REPAIR REQUIREMENTS 

By M. S. Bonura 

McDonnell Douglas Astronautics Company 

SUMMARY 



A primary mission objective of the SSS 90-day manned test was that all 
spares would be stored onboard with all required maintenance and repair 
tasks performed by the crewmen. This mission objective was met since all 
maintenance and repairs were accomplished utilizing only onboard spares. 

During the test, the crew performed 212 maintenance and repair tasks on 
the life support system (LSS) and over 40 maintenance and repair tasks on 
miscellaneous support equipment. The total crew time on the LSS was 
117.4 hours for repair and 34.4 hours for maintenance. The total crew time 
for all maintenance and repair tasks was approximately 203 hours or 
2. 3 hours /day. 

All LSS units were successfully repaired with the exception of the zero- g 
urine collector and the onboard AUis- Chalmers electrolysis unit. These units 
were shut down on days 6 and 20, respectively, when the onboard repair 
efforts could not restore operation. The test was completed using backup 
procedures and equipment for these functions. 

INTRODUCTION 



To ensure the successful completion of the 90-day test, extensive planning 
was required to determine the spares and maintenance actions necessary for 
continuous operation of the SSS equipment. The basis of this planning task 
was the failure mode, effects, and criticality analysis (FMECA). The results 
of the FMECA were used as inputs to a computer program which generated a 
spares inventory list which was then revie'wed by the responsible subsystem 
engineers for commonality of spares and for practical levels of component 
replacement or repair. The maintenance procedures were then formulated 
and the tool requirements and storage volume delineated. 

The test crew^ was required to monitor, maintain, and repair the life 
support equipment which was installed within the SSS. The only life support 
unit which was not installed within the SSS was an electrolysis unit which was 
deve^loped for NASA by the Lockheed Missiles and Space Company. This 
advanced subsystena was provided as a backup to the onboard AUis- Chalmers 
electrolysis unit and, due to space and time limitations, was installed outside 
the SSS. 

The approach to life support equipment repair and maintenance simulated 
that aboard a space station vehicle. The test crew was trained to complete 

513 




normal repairs, maintenance, and part replacement. Standby procedures and 
units were provided and used until repairs could be completed on the primary 
unit. All repairs and maintenance on inside equipment was accomplished by 
the test crew utilizing the onboard spares. Verbal assistance, when required, 
was provided by the outside staff. 

DISCUSSION 



The reliability of the equipment was generally very good. The only major 
failures occurred with the onboard electrolysis unit and the zero-g urine 
collector. A summary of the life support system (LSS) operation during the 
90-day test is shown in figure 1. The nonope rational periods for the wick 
evaporator, molecular sieve concentrator, toxin control, mass spectrometer, 
and baseline O2 control sensor do not signify failure but periods when opera- 
tion was not required and these units were in standby. A summary of LSS 
operating history is shown in figure 2. 

The major failures which caused unit downtime are as follows: 

A. Urine Collector— On day 6, the phase separator failed because of addition 
of excessive urine pretreatment which severely danaaged the separator 
impeller. The crew modified the unit for one-g operation. 

B. VD-VF— Between days 27 and 33, a malfunctioning boiler liquid-level 
control was repaired and the catalyst, which had been flooded with urine, 
was washed. On day 39 the condensate tanks, which had been micro- 
biologically contaminated by the flooding, were sterilized. Between days 
45 an,d 52, the catalyst was again washed and the unit sterilized after a 
malfunction of the urine accumulator liquid-level control. On day 81, the 
unit was shut down when the second boiler was expended. 

C. Solid Amine Concentrator— Between days 14 and 17 unsuccessful attempts 
were made to repair a faulty bed selector valve. The unit was returned 
to operation on the remaining two beds. Between days 20 and 25, the 
unit was shut down to evaluate lack of CO2 removal efficiency. Data 
evaluation revealed that the temperature reference junction had drifted 
15°F and required recalibration. On day 34 the pneumatic compressor, 
which supplied control power, failed and was replaced by a nitrogen 
pressure line from the two- gas control supply source. On day 81 the unit 
was shut down when acceptable CO2 levels could not be maintained in the 
SSS. 

D. Sabatier Reactor— Between days 14 and I6 the unit was in standby for 
evaluation of a suspected gas contamination problem. Nitrogen had been 
detected in the H2 and Freon had been detected in the C02» Between days 
17 and 27 the operation was intermittent with 25 shutdowns and restarts. 
On days 28 and 29 the catalyst was replaced. On day 59 the unit was in 
standby resulting from a lack of H2 and available crewtime for restart. 
On day 81a failed zero-g condenser separator was replaced. 



E. Allis-Chalmers Electrolysis— Between days 3 and 17 a failed rnod\ile was 
replaced and all modules flushed. In addition, repairs were completed on 
th^e electronic control and a N2 pressure regxiJator, Between days 18 and 
EO the operation was intermittent and final failure occurred on day 20. 

F. LMSC Electrolysis— Between days 1 and 3 the unit was in standby. On 
day 4 a H2 leak in module 1 was repaired. On day 9 operation was inter- 
mittent because repeated shutdowns of the 28- Vdc power supply. Between 
days 12 and 17 the unit was shut down to replace defective N2 purge 
solenoid valves and the 28- Vdc power supply. Between days 18 and 21 

the unit was in standby. Between days 45 and 48 the unit was shut down to 
repair a short in module 1, to repair leaks in modules 2 and 3, and to 
replace defective temperature switches. On day 6O a defective N2 solenoid 
valve was repaired and the 28- Vdc logic power supply was replaced. 
Between days 63 and 66 module 2 was rebuilt. Between days 73 and 74 
modules 1, 3, and 4 were rebuilt. 

The LSS repair operations requiring hardware removal, repair, and 
replacement during the 90-day test are outlined in figure 3. The crew was 
also requird to perform maintenance on equipment and the maintenance items 
which directly affected the LSS are also noted in figure 3. The hours noted 
are the best information obtainable from the test logs maintained by outside 
staff and crewmen. 

Since the LMSC electrolysis unit was located outside the SSS, all I6 repair 
operations on this unit were perform.ed by outside personnel. In addition, 
certain failures, which occurred in external gas sample and vent lines, were 
repaired by outside personnel. These items were the replacement of a flow 
transducer, the installation of a charcoal trap, and five charcoal changes in 
the Sabatier CO2 sample loop, the draining of water from the Sabatier methane 
vent pump, and the replacement of the O2 purifier in the electrolysis sample 
loop. These outside activities covered 25 items in 90.2 hours. Therefore, 
there were 152 onboard repair items which required 117.4 hours of crew time. 

In addition to repair and maintenance of the LSS, the crew performed 
additional tasks on onboard experiraents and other support equ^ment. The 
significant items are outlined in figure 4. Not included in figure 4 is the 
scheduled maintenance which was required for iteins such as the TV cameras, 
radiation monitor, and aerosol particle counters. This scheduled maintenance 
was estimated to be a total of approximately 23 hours. Therefore, the total 
onboard crew time for all maintenance and repair activities was approximately 
203 hours or 2.3 hours/day. 

As previously noted, all spares for the LSS and critical support equipment 
were stored onboard the SSS. The location and quantity were documented in 
the spares inventory list. There were 365 major items included in the spares 
inventory, not including items such as fluid fittings, wire, tubing, tape, and 
sealant. The usage of these major spare parts is noted in figure 5 and 
am.ounted to 14.3 percent usage of available spares. 



515 



CONCLUDING REMARKS 

The performance of the equipment was very good considering the system 
complexity and the extensive use of nonflight-qualified prototype equipment. 
The performance of the crew was excellent in completing the many repair 
and maintenance tasks. 

The stocked spares were sufficient to support the 90-day test except for 
those required for the urine collector and the Allis- Chalmers electrolysis 
unit. The use of the zero-g features of the urine collector were lost when the 
phase separator impeller was severely damaged on day 6. Unfortunately, this 
type of failure had not been anticipated by the FMECA and adequate spares 
were not available. Although two spare modules were provided for the AUis- 
Chalmers electrolysis unit, both spares were expended by day 20 and 
subsequent failures terminated the operation of this unit. 

The lack of adequate spares for these two units only emphasizes the 
importance of adequate reliability data. Analysis such as the FMECA is only 
as good as the available data. On new prototype equipment, this can only be 
obtained by extensive bench testing and long- duration tests such as the 
90-day test. 



316 



< 
So: 



o 
dec 

lUx 



oci 

5<SE 



ii 



Ul 



r 



S<ac 
hflci 
y uj 

< a. 

O 



z 

3 

i 

3 



i 



8: 

1^1 



O •" »~ *~ ^" 



M 



O 1- I- r- 



O O O T- •- 1- *>■ 



w«» 



u) u> eo lo 



loia in 10 



i»i lo ^ lo a 



M W ^ l>* ^ O ^ r- ^ ^» ^ O •- 0» ^ «- 



CM N N CM 



CM 



(S CM V- NCM 






CM CM 



«J '(f IS lO CO. 
cm' CM 






^ o o o o 



t» 



o o 



s 



iqc^ 



oooo 



CM 



§3^ 



to eo to 
in p*. I- o •- 

* te « « 

«- CM CM M 



CM 



«? 



t- CM 



estow 



I- »- CMCM 




CO 
K 
UJ 

Is 



o 

•1-1 

o 

CO 

w 



s 



03 



Ii 

Ul! 
CO; 



cgcgh-g, 
mmZgc : 

OOmui! 

111 lu PS3' 
uiuiFSi 



517 



» 



K 



a 

K 

■c < 



K < 



Ss K 



B a 

lU Sj 

u — 

< St 

£ i 



(M 


z 5 


> 


<■ "•. 


< 


.« f« 


o 


s «l 


z 
a 


S5 


K 
UJ 


M <0 


>- > 


^ 


< < 




a a 


a 


z z 


o 


o o 


Ul 


V> CO 




z z 


z 


S E 


Ui 


a a 


a. 


-J i^ 


X 


a o 


lU 


u u 


o 


Q Q 


Ui 


UI UJ 


u 


M U 


< 


< < 


~1 


^ ^ 


a. 


a. a. 


UI 


lU UJ 


K 


K cc 



(9 

NO 
OK 



caM 



(C-l 

gg 

UJZ 
Eo 

£^ 

ta< 
<> 

c/iui 



zz 
oo 



(MM S 

isi 

O Z o 

ec o oc 

CO UJ v> <■> 

>">->■ 

<< < < 

a r* Q Q 
zSi z Z 
oec o o 

Z»- z z 
OM o O 

K|_ cc cc 
UJ ^ UI UJ 

B. (J a. & 

o^oo 
to »- •- 

UJ*^ UI lU 
UJ t Ul UI 



>- 
< 
a 



< 

GC 
UI 






I 



1 



s 



a 

UJ 



+ 



H 



t 



rff" 



fe 



i i 

UI UJ 

ra -J 

<UJ ^ 

5= S 

So 

UI s £ 



>- 

oc K 

Ui UJ 

_l t- > 

t «=o si o 
3B o e iZ u 

UJ I- £ ~ UJ 

i" EC O a K 

S |"i£ 

s > "E Si 
C > £ = o< 

^ • S X a. £ 



^ UJ ^ 

;? UJ ^ S^ 

K — O C 

3 M £= Z 

UJ 5<S" 

ec s -I o -j 

UJ tf o u < 

cL o UI £ e 

S OSO E 

< 



oc 



< B 
X^i 
U UJ 

M ^ 



^ Z OC -I U , UI o 

-l5 H<->OUjZ 

m£ eauiujOMM 

sg MUjujF-Sto 

51 • • • 



UJ 



< 
> 
a 
< 



a 

O 
■1-1 

O 



0) 
CO 

CQ 

-M 

o 

Qi 

CQ 
0) 



I 

o 

CM 

o 

.1-1 



318 



«9 

mi 

P 



X 



NW 


ejnNCDa 


cd^ 


CO O (O u> <t 


<p- 


N «- 



Si 



oo 



<D iq cj ^. iq 



Z 
3 



uu 



«ee 



S^l? 



^m 



r^eo oo 



e^oou) o«- 






OC 

X 



If) 



o n o m r^ 
^ouidd 



md 



oo 



«- lO 

oooo« od 



ui 
I- 



UJ 



(M O 



^"g-- 



•- OO 



OOOOIO o«- 



d^ 






WW t- 

L ■ • • 

t-lO't 



om oo 



(OlOCf 



oooo 



fC 



(0 

lU 

»- 



NOO 



o o n (>) 00 



S^ 



1^ oo 



IS, (O oo o o 



S!^? 



z 
3 

H 
OC 



3 
(0 

UI 




Q OC S 

Uj gg 

=iflci«?<? 

I- p ~ -J -I 
UI F S m 09 



8 



z 

3 

s 

UJ 





^ 


2 


a' 


g 


i 

o 




UI 

u 


i 


1 


1- 


• 


oc 




i 




3 




«0 




UI 





>> 

u 



03 

a 

I 

a 

S3 



M 



OO 



1X4 



519 



LU O 
_J Z 

oi 

LU uj 

o z 



< 



OC 



to 



or 



to 



ir\ C3 !/> 

. . .00000000 
^ o» •— « 






OO^^rC3C3^0C>^0^ 



000 



• ••«•••• 

C3i— "OCSCDCJCMi— • 



NO 



CM 
CM 



ITS 

« 



^C3^CM»—«CVJ'— ••—••— «l/Ni—« 



Ql 



> 



< 



01 

< 

LU 
O 

QC 
U- 
UJ 

Of: 

I— 
to 
O 



to 
O 



o ^ 



o o 

O LxJ 

to Q^ 
< p 

I— o 



o 

°^ S ^ 






»r < 



o 
o 



CO 



CO 

< 



< 



00 



£ 



= o 

< 



< LU 

o o 
o o 

LU LU 

< < 

LU LU 
_! -J 

o o 



o 
to 

Q. 






^OLU 

i<^ 

O^ Q S 

Q < < 
LU oe: O- 

< o o 

> LU LU 



S < o < < 

Q^ Q. < Q- Q- 
O LU LU lU LU 



Z 3 O 

>^- 

qqS 

LU LU ~j 

O Ql Ij 
_J < h- 

Q- a. to 
^ ■ I 1 1 1 -^ 

ccoc — 



< 

to 

> 

U- 

Of: LU 
^ to 

LU »^ 

l±! > 

t LU 

< to 



to 

I* 

Q 






Pi 

0) 

I 

o 

.1-1 

a 

0) 

I 

o 

09 

CQ 
O 

i 

1— I 

1—! 

o 

09 
I 



520 



r_4 ■— « I— • i—i CMi— <CMi— «■-H^C^Jl/^ 



< 



CO 



a: 

< 
a. 



to 



to 
to 

< 



Si 

0£L I- 



to 

I— 

< 

il! oc 



i 



^2: 

^ OQ ^ 

UJ S l^ 
to LU ixJ 
to to Q^ 

< to O 
uj a. Q- o. 



o 
o 



o 
o 



O =3 



< o < o 
o o o o 

o ^ c^ o 2- Qc: 

< to >^ < to •"; 



ooo-oo::tL.ock:u. 



o 

o 
fctf 



a. 
o 













>- 










—J 


0£ 












o 


—1 


o 




Ol 






(^ 




o 




t- o 


1— 




i— 


u- 


UJ 




NAGEMEN 
ODE 
COLLECT 


1 

UJ 

o 

< 




8 


i 

UJ 


oc 

1 


UJ 








=J 


oc 


iii 


i 


u. 

> 
1 


CO 


to 


< 


UJ O Q^ 




> 


=3 


£ 


§ 


o 

UJ 


< 


< 










d 


^ 


^ 










.< 



<1> 

CQ 
(0 



09 
T3 

I 

O 

U 
O 

I 

I 

O 



E^ 



V) 



521 



< 



Of; 

< 

CL 



«/l 



i-H •— * CM CM CM •— • 



O 



« 

o 



ixJ 

> 
^ > ^ 

=3 O < 

> 



uj 2j, »*. ^^ 

tii ^ ^ ti l^ o 

_ O —I 5 O X 
Ix. O CO ^ CO O 



O 

o 

IxJ — 

Q^ c^ ^ 

tTJ <^ ?:i 
>- Z g 

^ Uj DC 
O O LU 



QC 
Q 



Of: 
O 



5 00 
Iji IxJ CL 

Q Qi < 
O ixl Of 

Q =3 o 

C^ to Qi 

uj to < 
Z UJ -J 

u O:: O 
M Q. Q. 



1— 1 f— « 


CM 




ITN 


LU 




OQ 




=3 




I— 




ai 




LU 


LU 


. . -J 


OC 


TUBE 
ILTIP 


< 

to 



O , O 
> Q- 



O. 
O 



OC 



< o 

E8 

QC lu 
ID Z 
Q- — 



I 

Of: 



to 



OC 



< 

to o 
O to 



LU OC 

o i 

LU 

to Q_ 

fv» ^ 

< *^ 

B-J LU 

=3 oe: 

O LU 

LU z 

O CO 

S o 



< 

LU 
OC 

OC 
Z tu 

<i 

ZD 

to 



I 

to 



< 

to 

to .^ 
>- to 

O LU 

o < 
ax 

LU O 



to 

OC 
O 

to 



to 

to 

< 



OC 

o 

to f: 



to 

LU 

< 

Q_ 

to 



»— t 

u 
a 
o 
O 



bfi 

•r-t 



7=- O 



?^5 

=: ^ => 

to ::j s 

< lu o 

OQ O O 

to 



O E 



< 

01 



522 



EEVELOBiEET OF CEEMf SELECTION GUIEELIBES FOR THE 90-riAr MAUHED TEST 

Eiy Eayford T. Saucer 
NASA langley Research Center 



SUMMAET 



A panel or steering committee of "behavioral scientists was created to 
advise NASA AND MDAC operations personnel on selection methods for the crew. 
The panel, acting in an advisory capacity, made recommendations concerning crew 
selection, monitoring, and assessment. A generalized concept of crew selection 
for long duration missions was developed on the hasis of motivation, skill 
levels, emotional maturity, and ohservations of group compatibility. 



IimiODUCTION 



The plan for the 90-day manned test was to minimize the passing in or out 
of materials, to avoid opening the test chamber except in case of emergency or 
total systems failure, and to make maxt.mal use of the onboard crew for operation, 
maintenance, and repair of the life support systems. These and other constraints 
indicated that the crew would xuidergo a high degree of physical confinement in a 
relatively small space for the duration of the test. 

The triad of confinement, isolation, and monotony is potentially stressful 
for many people. While it was expected that the confinement aspect of the test 
would be real, preliminary study indicated that the communication^, flow would 
be high and that the activity within the chamber would be diversified. With a 
four-man crew and a high communications flow, isolation per se seemed to pose 
no real problem. The varied activity within the chamber suggested that the 
mission would not become monotonous. The absence of these two factors (isola- 
tion and monotony) tended to focus concern on the motivation of the individual 
crewmen and the psychosocial integrity of the crew. Low motivation and inter- 
personal stresses arising from relative confinement, low habitability, and 
incompatibility could conceivably precipitate a crew- initiated abort. Such an 
action wpxild result in a consequent loss of a large amovint of engineering data. 

In many ways the successful I969 Tektlte 1 study (ref. 1) seemed to offer 
a conceptual model for the 90-day manned test. In this study four marine 
scientists remained below the ocean for 60 days while executing a variety of 
research projects. Except for the degree of freedom allowed by relatively short 
periods of escploratory diving, the habitat and task loading for the Tektite 1 
study were similar to those projected for the 90-day test. The crew members 
were primarily responsible for the planning of the oceanographic research and 
for gaining acceptance of the program within the Department of Interior, where 
they were employed. They had formed an ad hoc group of like-minded individuals 
who were convinced that serious marine research could be carried on by using 
sat;iration diving techniques. In addition, each member of the group had a 

523 



strong personal interest in a particular area of oceanography and was motivated 
"by the prospect of publishing important technical and scientific papers in his 
area of interest. 

Overall results of this effort suggested that a small group can form a 
viahle mLcrosociety and withstand "both individixal and interpersonal stresses if 
individual motivation is high, if the group is compatihle, and if there is a 
supraordinate goal to hold the group together. It seemed feasible, therefore, 
to apply sqme of these emerging concepts to the problem of maiming the 90-day 
test. 

These concepts, together with work by Sells in establishing models of 
microsocieties (ref . 2) and unpublished work on interpersonal compatibility by 
¥. W. Haythome and Seward Smith of the Naval Medical ^Research Laboratoxy, 
offered the possibility of formulating a crew selection procedure with definite 
goals. The goals of the selection procedure were to minimize the possibility 
of a cre-w- initiated abort, to minimize the effects of stress on the individual 
crewmen, and to offer a realistic reward for successful completion of the 
niission. 



APPROACH 



The behavioral program for the 90-day test was seen not as a trial of 
human endurance but rather as an atteii5)t to aid the success of the mission by 
supplying knowledge of small-group processes and dynamics. 

A panel of experts in small-group dynamics was assembled. Operations 
personnel from the National Aeronautics and Space Administration and from 
McDonnell Douglas Astronautics Company were included in the meetings so that 
direct contact with the project could be established and maintained. 

An exploratory meeting was held at NASA. Langley Research Center and a 
definitive meeting was later held at Texas Christian University. During the 
first meeting it was decided that the panel could best serve in an advisory 
capacity to the NASA and MXAC. The panel felt that it would be able to help 
provide a rationale for crew selection, monitoring, and final assessment of 
crew status. The second meeting addressed itself to both the problem at hand 
and the extended problem of small crews for long duration missions in general. 
The report of this second panel meeting has not yet been formally published; 
this delay is due, in part, to the fact that informal communication between the 
panel, NASA, and MDA.C was ongoing iintil the final selection. Since the second 
meeting was held some time before the final selection, it may be that seme ideas 
which were emergent during the meeting became more definitive at later stages. 
The present paper reflects most of the spirit and substance of the panel meetings 
with perhaps some slight changes in emphasis and with some reorganization. 



32k 



nnscussioN 



The suggested method of iniplementing the goals of the selection procedure 
can he outlined. 

The most important factor in selection was believed to be motivation. In 
the present context motivation was defined as career motivation; that is^ the 
mission participation would be seen by the individual as an opportunity which 
would significantly affect his future career. Thus, it was suggested that 
university graduate students majoring in technical areas relevant to the 90-day 
test would provide an appropriate subject pool. This recoramedation was adopted, 
and a prospectus was circulated to major xiniversities within the Los Angeles 
area. Over 30 responses followed. It is likely that more could have been 
secxired had the prospectus been circulated nationwide. 

Pursuant to the present definition., motivation could be assessed by active 
career interest and a relevant educational program, by academic standing, by 
faculty recommendation, and by interviews. 

During the course of continuing interaction between the panel and the oper- 
ations, personnel, it became evident that much of the Success or failure of the 
mission would depend upon engineering, mechanical, and technical skills and 
aptitudes of the crew. A task ana;lysis was suggested, to be followed t^ defini- 
tion of jobs or task areas. Selection procedures could then be defined in terms 
of relevant study areas, work history, and interest patterns. Further evalua- 
tion could be carried out dttring the systems tj^aining period before the final 
crew was chosen. 

The next definitive step involved a medical examination and assessment of 
psychological health and emotional maturity. None of the selected crewmen had 
a history of a major physical disease and none had evidence of psychiatric dif- 
ficulty. After Some members of the odriginal pool had withdrawn because of 
academic schedules or other pressures, the remainder were administered a com- 
prehensive psychodiagnostic battery by a licensed clinical psychologist. The 
scores were then forwarded to the panel for study and conciirrence. 

Given active motivation, relevant work history, and personal stability and 
emotional maturity, group canrpatibility became the desired objective. This 
objective in fact was combined in part with the final step, selection of the 
crew by c^erations personnel. It was felt that the decision of the operations 
personnel wouM profylde a backup to the other procedures and would probably 
provide the best assessment of work skills. In addition, since the onboard 
crewmen would be continuously working with each other and with the outside crew, 
an opportunity for observation of group compatibility would exist. 

The panel also recognized the fact that the onboard crew would be Integrated 
into a complex organizational and technical structure. It therefore recommended 
several constraints in this area. For example, it was believed that some nec- 
essary degree of structure might be obtained by designating a crew chief. It 
was suggested that he be selected before the beginning of the test but as late 
as possible so that his leadership potential and acceptance could be evaluated. 

525 



It was recommended that if at all possible, lie lae the older, more experienced 
member of the crew with some e3q)erlence in total systems concepts so that status 
congruence could he presearved. 

In order to achieve a useful simulation, it was recommended that the simu- 
lation he characterized as an experimental test of a prototype space System and 
that the major task of the crew he defined as the operation, maintenance, and 
repair of the system. All irrelevant tasks were to he eliminated if possihle 
and only tasks relevant to a real life work situation were to he retained. If 
possihle, the onhoard crewmen were to he Integrated with operations personnel 
in such a way that they would share a common goal of completing a significant 
engineering experiment. It was also suggested that some opportunity he provided 
for the crew to design and carry out hona fide research projects during the 
mission. 

Unally, it was suggested that all relevant aspects of the aiission such as 
the necessity for hehavioral studies, tasks, and ohservations he frankly and 
openly discussed with the crew so as to avoid misunderstandings and surprises 
during the course of the test. 

In post- test discussions with hoth MASA. and MMG project managers, the 
panel ascertained that the crew met the Managers' expectations with regard to 
psychosocial integrity and with regard to performance. They responded weU to 
hoth emergencies and prolonged repair and maintenance tasks. Such minor onhoard 
problems in interpersonal relationships as occurred were prohahly negligible in 
their effect on the total systems operation. At no time was there any pronounced 
schism between the onboard and outside crews. 

This ccii^patibility may have been in paart due to the emational matixrity of 
the onboard crew and in part due ta same evident feeling that the onboard crew 
was an elite, intelligent, and knowledgeable group of individuals. 

CQWCLUnENG REMABKS 



It is quite possible that the recomtendations of the panel were too gen- 
eral, but the intent was to provide a generalized schema of crew selection with- 
out defining the actual selection program, in detail. In review, the schema pro- 
vided cannot be said to be novel. It consisted of plans to choose highly moti- 
vated individuals who had the requisite work skills, emotional matijxlty, and 
group compatibility to withstand the mission stresses and to execute the task 
of operating the onboard systans. These qualifications were assiired in part by 
formal testing and examination and in part by critical on-the-job selection. In 
retrospect, this schema should apply in general to personnel selection for 
hazardous or dem;anding missions.. 

If the schema was successfxxl for the selection of the crew for the 90-day 
test, a large part of the success was due to the close cooperation between the 
behavioral science community and the responsible HASA and MDAC project managers. 



526 



mFEEENCES 

1. Clifton, H. Edward; Mahtdten, Conrad V. W. j Van Derwalker, John C. ; and 

Waller, Ei chard A,: Tektite 1, Man-in- the-Sea Project: Marine Science 
trogram. Science, vol. l68, no. 5952, May 8, 1910, pp. 659-665. 

2. Sells, S. B. : A Model for the Social ^stem for the Maltj m a n Extended 

Dturatlon Space Ship. AeroSp. Med., vol. 57* no. 11, ITov. I966, 
pp. 1150-1155. 



527 



CREW SELECTION 
By J. S. Seeman and M. V. McLean 
McDonnell Douglas Astronautics Company 

SUMMARY 



The successful selection of crewmen for the 90-day manned test was 
a m.ajor contribution to the total study. A highly selected group of indi- 
viduals w^as screened and evaluated for compliance with numerous criteria 
relating to their acceptability and ability to withstand isolation stresses. 

Results of the crew selection process indicate that crew selection was 
an important contributor to the overall success of the 90-day test. In 
addition, quantitative psychological criteria have been developed which can 
be employed on future studies of this nature. 

Certain limitations in the use of psychological testing techniques have 
been identified and the importance of pragm.atic aspects of personnel selection 
has been demonstrated. 



INTRODUCTION 



Crew selection for the 90 -day test was the most comprehensive selection 
program ever applied to a simulation study. The selection program had the 
objective of choosing a crew that would function effectively and efficiently for 
the total test duration and do so with no subsequent pathology. Selection 
techniques were psychologically oriented, but also placed a great deal of 
emphasis on the more pragmiatic aspects of crew suitability such as mechan- 
ical skills; availability for training; physical fitness; health of close family 
members; motivation for participation; and acceptance of pay scales offered. 



529 



PROCEDURES 



Three lines of selection were followed: psychologiqal, physical, and 
pragmatic. Criteria were developed within each area. Throughout the multi- 
stage selection process, consonance of volunteers with these criteria was 
sought. An overview of the selection process is presented in table 1. 

Psychological Criteria 

At the request of the contractor, a NASA- sponsored symposium was held 
at the Institute of Behavioral Research, Texas Christian University, to 
develop criteria and procedures for crew selection. Symposium panel mem- 
bership consisted of the following personnel: 

E. K. Eric Gunderson, Ph. D. 

Director, Special Environments Division 

US Navy Medical Neuropsychiatric Research Unit 

San Diego, California 

William. Haythorn, Ph. D. , Director 
Behavioral Sciences Department 
Naval Medical Research Institute 
National Naval Medical Center 
Bethe s da, Ma ry land 

R. Mark Patton, Ph. D, 

Chief, Human Performance Branch 
NASA Ames Research Center 
Moffett Field, California 

James R. Rawls, Ph. D. (Now at Vanderbilt University, Nashville, Tennessee. ) 
Associate Research Scientist 
Institute of Behavioral Research 
Texas Christian University 
Fort Worth, Texas 

Rayford T. Saucer, Ph.D. (Co-chairman) 
Consultant 

Stop 310, NASA Langley Research Center 
Langley Station, Hamipton, Virginia 

Mr. Jerorae S. Seeman 

Behavioral Director - 90- Day Manned Test 
Advance Biotechnology and Power Department 
McDonnell Douglas Astronautics Company 
Huntington Beach, California 



550 



Walter L.. Wilkins, Ph. D. 
Scientific Director 

US Navy Medical Neuropsychiatric Research Unit 
San Diego, California 

S. B. Sells, Ph.D. (Co-chairman) 

Director, Institute of Behavioral Research 
Texas Christian University 
Fort Worth, Texas 

The resulting recommended process was a multistage screening 
necessitating demonstration among crew candidates of: 

A. Scientific and technical skills and capabilities. 

B. Emotional maturity and mission motivation. 

C. Physical health. 

D. Ability to withstand isolation. 

E. Leadership identification. 

F. Crew compatibility. 

Information concerning quantitative scores of the various psychological 
tests for each of these areas w^as not available. Consequently no quantitative 
criteria existed for crew selection based upon psychological tests and what 
was recommended consisted of a technique of multiscreening based upon 
indgment of the screeners. 

A consultant in clinical psychology (Dr. T. MacFarlane) administered 
tests, scored them, and recomnaended candidates from ajcnong those appli- 
cants sent to him for psychodiagnosis. Dr. MacFarlane generated, by MDAC 
request, a quantitative profile of scores on the various objective psycho- 
diagnostic tests, which were on an a priori basis thought to describe the kind 
of person expected to be most effective in withstanding the rigors of 
confinement. 

Physical Criteria 

Physical criteria consisted of the ability to pass an FAA Class I physical 
examination and demonstrated compliance with norraal values of a number of 
biochemical indices. 



331 



Pragmatic Criteria 
Pragmatic criteria included: 

A. Willingness to volvmteer for the entire program.. 

B. A demonstrated life style indicative of inner-directedness with little 
dependence on other persons for emotional stability. 

C. No criminal arrests or convictions. 

D. No serious speech impediments. 

E. No evidence that participation in the program reflected an escape from 
life. 

F. No previous history of serious emotional difficulties. 

G. CommitmLent to the achievement of higher academic goals in graduate 
school. 

H. Interest in becoming an astronaut. 

I. Previous history of small group confinement or isolation experiences. 

J. Experience with construction, repair, and/or maintenance of electro- 
mechanical devices. 

K. Older than 21 years. 

Li. Height and weight consistent with volumetric provisions of SSS. 

M. Minimal history of psychosomatic Illness. 

N. No serious physical illnesses among close relatives or friends. 

Applications were solicited from graduate schools in the Southern 
California area within the disciplines of engineering, physics, biology, and 
the social sciences. Contact was established between representatives of 
MDAC and the personnel offices at the various universities. These contacts 
permitted an explanation of the 90- day test to be relayed to officials of the 
schools and also afforded the opportunity to request that applications for 
membership in the candidate pool be limited to those graduate students whose 
major professors would recommend and concur in the application. Approxi- 
mately 45 applications were received. 

The 27 who survived the initial screening and appraisal interviews were 
identified on the basis of initial screening and approval interviews by the 
Behavioral Director, as well as through review of screening questionnaires 
obtained before the interviews. Reasons for exclusions from this group 
included monetary incentives being primary as a motivational force in volun- 
teering, imminent school failure, ill health of close family members, history 
of serious emotional difficulties, etc. 



552 



Psycho- diagnostic tests (objective and projective) were next given to 16 
individuals identified as most desirable of the 27. Test profiles were 
developed by MDAC and its consultant at this point, which were thought to 
be descriptive of the "classical" crewman. Accordingly quantitative values 
were established consisting of ranges -wherein each applicant's scores should 
fall. Objective tests given w^ere: 

A. MMPI (Minnesota Multiphasic Personality Inventory) 

B. FIRO- B 

C. 16 PF (Forms A and B) (16 Personality Factors) 

D. MAT (Motivational Analysis Test) 

E. Study of Values - AUport /Vernon 

F. Edwards PPS (Personal Preference Schedule) 

G. Rokeach Dogmatism Scale 

H. Eysenck Personality Inventory 
Projective tests used were: 

A. Rorschach 

B. Thematic Apperception Test 

C. Sentence Completion 

D. Early Parental Recollections 

E. Future Autobiography 

The formial crew pool (eight) was chosen on 26 January 1970, Training 
began the following week. Throughout the training period the men were 
observed for group formation and the evolution of a leader. Immediately 
prior to the S-r-day run, a sociometric test was given as an adjunct to aid in 
crew selection. This combined with training results and, to an extent, indi- 
vidual availability led to the selection of a four-man crew. Crew performance 
was outstanding during the trial run and gave a great deal of confidence in 
the selection process. 

Subsequent to the 5- day run, a review and evaluation was accomplished 
that gave valuable information for hardware and procedural modifications. 

Final crew selection occurred on 26 May 1970 and w^is achieved through 
the consensus of the Program Manager, Medical Director, and Behavioral 
Director following an evaluation of all the pertinent data, i. e. , training 
results, psychological data, subsystein knowledge, health data, etc. 

333 



RESULTS 

Table 2 presents an overview of the major findings of the selection 
effort. The success of the selection program is attested to by the fact that all 
four men selected withstood 90 days of confinement with no serious hostilities 
developing and no indication of any intent to abort the mission. All scheduled 
tasks were performed throughout the 90-day period promptly and 
cons cientious ly , 

Following the 90-day test, initial review of objective psychological 
test results indicates that there is no apparent consequent pathology. Pro- 
jective tests are scheduled for the immediate future, but no surprises are 
expected. 

Selection criteria for the objective psycho- diagnostic tests have been 
developed which are quantifiable and apparently valid. This is considered 
to be a major contribution to future quantitative crew selection procedures. 
The objective of scientific and technical capabilities was obviously met as 
the crew learned the subsystems and they operated well with outside crew 
support. 

A feature of selection not originally planned, but of considerable value 
in the ultimate selection, was the demonstrated ability of selected candidates 
to comply with the many irritating, time- consuming, and constantly changing 
infringements on their time throughout the training program. Crewmen were 
thus additionally selected on the basis of accepting these requirements without 
complaint. 

Another feature originally intended to be used (observation of group 
structure throughout training) proved to be of less value than originally 
expected because a cohesive group was not firmly developed. Attention to 
the personality characteristic of inner-directedness during the selection 
process apparently worked toward mitigating the development of a strongly 
cohesive group. These individuals were too inner- directed to permit the 
penetrations necessary for the establishment of such a group. 



CONCLUSIONS 



Crew selection is not a highly exact process of matching test results 
with pre-existing criteria. Throughout selection, human judgments and 
hypotheses as to acceptability must be continuously advanced, discussed and 
reevaluated. Because no test or group of tests yet exists which can be 
totally relied upon, iterative consensual human judgment and intuition serve 
as the primary selection mechanism. Thus, selection of the selectors looms 
as of paramount importance in the accomplishment of successful crew selec- 
tion of memibers of long-duration space missions. 

A great deal of time was necessary to the selection of the crew. It is 
felt that too much emphasis was placed upon psychologically based crew 
selection techniques which is inconsistent with the degree of confidence cur- 
rently existing in the adequacy of these techniques, 

55^ 



The points already made emphasize the tenuous nature of existing 
psychologically based crew selection techniques. It would be highly 
desirable to explore the possibility of increasing the validity of selection 
methods. Rather than reexamining and validating psychological selection 
tests, it seenas more reasonable to investigate alternate selection techniques 
deriving from other disciplines. 



555 



TABLE 1.- CREW SELECTION 

OBJECTIVES 

HOMOGENEITY OF PERSONALITY CHARACTERISTICS 

HIGH MOTIVATION 

PRECLUSION OF CONSEQUENT PATHOLOGY 

ABILITY TO LEARN SUBSYSTEM OPERATIONAL REQUIREMENTS 

ELIMINATION OF INTER-CREW HOSTILITIES 

EMOTIONAL STABILITY 

PROCEDURES 

• FORT WORTH SYMPOSIUM -- RECOMMENDED PROCEDURES (21, 22, 23 MAY 1969) 

• LIMITED APPLICATIONS - GRADUATE SCHOOLS AND DISCIPLINES (OCT 1969) 

• APPRAISAL INTERVIEW -- AVAILABILITY, INTEREST, HISTORY, AND OBVIOUS 
PHYSICAL INCOMPATIBILITIES (NOV 1970) 

• SCREENING TESTS -- MDAC, NMRI, AND NMNRU (DEC 1969) 

• PHYSICAL EXAMS (JAN 1970) 

• PSYCHODIAGNOSTICS - DEVELOPED QUANTITATIVE CRITERIA (JAN 1970) 

• IDENTIFICATION OF CREW POOL (26 JAN 1970) 

• TRAINING, INCLUDING COHESION TRAINING (STARTED 2 FEB 1970) 

• EVALUATION OF TRAINING AND CREW FORMATION ~ TESTS AND OBSERVATIONS 
(JAN TO APR 1970) 

• SaECTION FOR 5-DAY MISSION (APR 1970) 

• REVIEW AND EVALUATION OF 5-DAY CREW PERFORMANCE (8 TO 15 MAY 1970) 

• SaECTION FOR 90-DAY MISSION (26 MAY 1970) 



^36 



Table 2 
RESULTS OF CREW SELECTION PROCESS 

Achieved fair homogeneity of personality characteristics 

High motivation 

No apparent consequent pathology 

Identification of apparently valid and numerically 
describable selection criteria 

Excellent learners-Subsystems operated with crew support 
Minimal manifestations of crew hostilities 



557 



CREW TRAINING 

By R. E, Shook and J. S. Seeman 

McDonnell Douglas Astronautics Company 

SUMMARY 

The purpose of the crew training program was to prepare candidates for 
effective participation in the 90-day manned test. Curriculum coverage 
was accomplished over an approximate 6-month period and consisted of train- 
ing in experiment operations, safety procedures, equipment operating proce- 
dures, and maintenance and data collection requirements. 

The training program contributed significantly to the success of the 90 -day 
manned test insofar as it provided a well-trained, highly motivated crew for 
integration with the operations required onboard the Space Station Simulator 
(SSS). 

INTRODUCTION 



The goals for training at the beginning of the program^ emphasized the need 
for crew connpetence and safety. The basic requirements included candidates 
with good basic scientific training and aptitudes, experienced instructors, a 
thorough curriculum, and a flexible schedule. The preliminary organization 
of instructor staff and curriculum development is dependent on staff experience 
and abilities and can be formed in a relatively straightforward manner. After 
development, the training program becomes dependent on the availability of 
the staff, crewnaen, and training equipment, all of whom have other demands 
on their time and attention. The development and use of an accommodating 
schedule permits maximum interaction of the crew and instructors. 

PURPOSE 

Crew training served the dual functions of providing information to the 
crew on test objectives and operational requirements, as well as providing 
information on the crew regarding levels of motivation for use by program 
management as pragmatic inputs to crew selection. 




559 



ORGANIZATION OF TRAINING 



The organization of training began with the appointment of a training staff 
consisting of a training director and instructors for each course. The Program 
Manager, with the Behavioral Director, appointed the staff of instructors and 
the training director. The training director reported to the Behavioral Direc- 
tor and was responsible for curriculum development, scheduling, and all crew/ 
staff interactions. The training curriculum was developed by each instructor 
submitting a course outline that specified subject matter to be covered and 
performance requirenaents for the crew candidates. The preliminary schedule 
was developed by the staff from these outlines and the scheduled development 
of the test equipment. 

CURRICULUM 

The basic curriculum consisted of lectures, demonstrations, and practice 
sessions. Lectures were used to familiarize the crew with equipment oper- 
ation and maintenance, medical and behavioral methodology, test procedures, 
and requirements. There were three basic areas in the curriculum: (1) bio- 
medical, (2) life support systems, and (3) man/ systems integration and 
operation. 

The distribution of course work under these headings can be seen in 
table 1 and Appendix A. 

The crewman performance evaluation for this curriculum consisted of a 
crew proficiency rating (table 2) filled out by each instructor after the comple- 
tion of his class and evaluation period, a crew course rating filled out by the 
crewman candidates (table 3), a self-evaluation by each candidate of his own 
knowledge of the systems ^ and three written tests administered periodically 
during the course of training. 

The first of the three written tests was relatively unstructured and 
requested that the crewmen describe what they knew of the systems they had 
studied and what they understood of the objectives of the 90-day test. The 
intent in giving this type of test was to assess the effectiveness of the training 
to date, to find those areas the crewmen were interested in and responded best 
toward, and to see how each crewman structured his concepts of the whole 
prograna; i. e. , whether he responded with detailed analyses of the equipment 
and processes or was concerned with the larger view. The crewmen's scores 
on this test were not used for comparative evaluations because they responded 
in different ways. Some went into little detail system by system, but gave a 
good comprehensive view of the program. Others provided considerable 
detailed description of the processes and hardware of the life support equip- 
ment. These differences had a beneficial effect because in this competitive 
situation it demonstrated the various viewpoints and grasp of detail possessed 
by other candidates and clearly defined the nature of the selection competition. 
The second written test concerned the life support systems and asked for 
details of hardware and processes. The last test was, in effect, a final 

3to 



examination consisting of questions submitted by instructors from areas 
requiring detailed system descriptions and procedural miethodologies. This 
last test and the instructors' evaluations were given the most weight in evalu- 
ation of the candidates. 

The candidates were graduate students frona several local universities and 
adapted very readily to the laboratory and the type of training. (Their graduate 
studies were more arduous than the simulator training. ) All of the candidates 
had had previous training that was directly applicable to some area in the 
program. One candidate was experienced in veni-puncture techniques and 
blood handling, several had taken bacteriology classes, and all had taken 
sufficient chemistry courses so that they readily understood the life support 
processes. All had had experience in operating test equipment and computer 
techniques. Their advanced degree goals in engineering and the sciences also 
demonstrated the very important attribute of being concerned with this type of 
prograna, the experiments, and knowing the value and need of good data. 

Cross -training of the crewmen was quite extensive in the first part of 
training. All members of the final group practiced veni-puncture techniques, 
urinalysis, and sterile techniques for microbiology. All attended the lectures 
on life support equipnaent and practiced the man/ system procedures and 
psychomotor devices. 

Cohesion training was a form of sensitivity training oriented to the develop- 
ment of a cohesive group consisting of crewmen and com.m.unications mionitors. 
It was undertaken in an attempt to eliminate intercrew difficulties. Cohesion 
training consisted of six sessions of varying length. The first session was 
6 hours long with seven crewmen and four communications monitors partici- 
pating. The group director was an MDAC consultant. Dr. MacFarlane. The 
last session consisted of eight crewmen, two communications naonitors, and 
Dr. MacFarlane. 

As training progressed and particularly after final crew selection, the 
amount of cross -training was lessened, and with some experiments none was 
done. The particle counting experinaent procedure, light measurement, 
and naass balance data management were assigned to particular crewnaen. The 
microbial monitoring technique was taught to two crewmen. Two crewmen 
were selected for EEG monitoring and taught the required procedures (paper 
no. 38 of this sjmiposium) . 

The following chart shows the training hour distribution. All values are 
in naan-hours. 

Lecture and Miscellaneous Written Total 

Demonstration Practice (EEG Sleep) Test Training 

853 893 44 80 1, 870 

There was somie difference between crewmen in the number of hours each 
attended training. After crew selection, there was more demand to train 
those selected in particular fashions relating to their anticipated onboard roles. 

5iH 



The scheduling of training was the most persistent problem throughout the 
pretest period. In the beginning of the training period, the class schedules of 
the crewmen became the controlling factor for their training schedule. The 
class schedule factor gradually diminished because those crewmen with large 
class and workloads withdrew from school as they becanae more involved in 
the 90-day test classes. Another type of scheduling problem appeared and 
remained throughout the training period. This was the coordination of crew 
time with the instructors involved in the process of developing, testing, and 
installing a piece of life support equipment. Occasionally, an early lecture 
and demonstration would have to be redone when the equipment was modified 
after additional testing and instrumentation and other devices added. 

Biomedical and man/ systems experienced relatively little difficulty in 
scheduling of training. The demand for practice tinme by some of the equip- 
ment, such as the ergometer and human describing function device, could not 
be met on all days because of limited opportunities for demonstrations and 
practice on other equipment. As blood analysis was begun, the crew arrived 
in a fasting condition every Tuesday morning and practiced blood and urine 
sampling, microbiological techniques, food managenaent, andwaste material 
handling. The requirement to arrive fasting every Tuesday morning depended 
upon the crewmen and was met with few exceptions. This type of coordination 
was more the exception thani the rule. 

Occasionally, the availability of a particular instructor or equipment 
required rescheduling of a class and the reduction in the number of crewmen 
given certain kinds of training. This was true of the electrolysis units and 
the solid amine CO2 concentrator because other companies developed these 
units and assisted in the crew training. Some computer training was given 
after regular work hours to have more nearly uninterrupted access to the 
computer. i 

Maintenance training was variable for each item. On some items, instal- 
lation and instrumentation occurred late in the prerun period and the available 
training time was used to teach operation. Major overhaul type maintenance 
was not taught as it was felt that most equipment would operate with only minor 
electrical andmechanical malfunctions. Some units had a considerable history 
of operation without failure before, the 90 -day test. In-depth maintenance 
training was not practical for most of the life support equipment because of the 
complexity of their respective control systems. The Schedule seldora per- 
mitted adequate time to pra,ctice maintenance on equipment undergoing final 
test, instrumentation, and installation. 

In the biomedical lectures and demonstrations, there were few or no diffi- 
culties and the practice requirenments allowed adequate scheduling flexibility. 
Similarly, the man/systems lectures and denaonstrations introduced few 
difficulties and permitted flexibility in scheduling. The final sessions of 
cohesion training had to be postponed once or twice. This apparently had little 
impact on the class. Practice on the psychomotor devices was interrupted 
while they were being installed in the simulator, but this was a relatively small 
amount of time compared to the whole practice time. 



3h2 



The life support systems presented the most difficulty in scheduling. 
Lectures and denaonstrations depended on the performance and acceptance of 
the equipment. It was intended to operate and practice maintenance on instal- 
led units. This was possible on some of the units, the thermal control for 
example, but on others, because of time constraints, lectures and demonstra- 
tions were accomplished outside the simulator. Some units were started up 
outside the simulator and then again after installation, with maintenance 
practiced after the pretest 5-day run. 

The instructors for the three areas of training were drawn frora the 
respective branches of the MDAC Biotechnology Department and from other 
contributing companies and Government agencies. The instructors for the 
biomedical and man/systemis areas were specialists in those disciplines appli- 
cable to specific classes. For example, a specialist with radiological training 
and experience was assigned to isotope handling. The instructors for the life 
support equipment were the principal investigators for each piece of equipment. 
The instructors outside MDAC were generally the principal investigators or 
their assistants for those experiments and pieces of equipment. 

The previous test experience of the instructors was invaluable because it 
provided a base of knowledge of what would be required. They devoted con- 
siderable extra time to course preparation and outside working hours instruc- 
tion, demonstration, and testing of the crewmen. Generally, they appeared to 
take personal interest in the preparation of the crew. 

The instructors were evaluated by the crewmen on the crew course rating 
(table 3) form (and by occasional remarks). These results can be employed to 
improve the content and delivery of future comparable training programs. 

A tabulation of MDAC capabilities brought to bear upon training for the 
90-day test is shown in table 4, 



CONCLUSIONS 



The training program was a contributing factor to the successful accomp- 
lishment of the 90 -day test. The performance of the crew throughout the run 
showed little of those characteristics of ineffectual training, such as operating 
indecision, poor or hasty procedural judgments, missed data, and over- 
dependence on outside direction; especially as the mission progressed. With- 
out competent crewmen, interested in and responsive to the needs of principal 
investigators and engineers, the 90-day test could not have been successful. 

For long-duration simulations of this type, a training program must be 
flexible with respect to schedule and changes in subject miatter. The subgoals 
of these studies evolve throughout the preparation period. The equipment 
design and installation schedules must be altered and access periods to these 
units changed. All these contribute to changing the training curriculum in 
content and in schedule. 



3h-3 



In the case of graduate students, the program schedule should accommodate 
the school schedule as far as is possible. Matching of subjects' aptitudes to 
the program reduces training problems on both ends of the spectrum. 

In addition to adequate subjects and a flexible program, experienced 
instructors further ensure an adequate training prograna. They know what is 
required, how to transmit this information to the subjects, and how to evaluate 
performance. 

In future training programs it may be desirable to compress and concen- 
trate training over a shorter period after subsystems have been received, 
installed, and integrated. This could significantly improve the adequacy of 
remedial maintenance instruction which during the 90 -day test consisted 
essentially of on-the-job training during early stages of the test. 

Cohesion training seems to have been effective in reducing the frequency 
and the severity of intercrew difficulties. Post-test interview material 
suggests that crewmen would have preferred to have had greater exposure to 
the cohesion training portion of the overall training program. This finding is 
consistent with results obtained on the 60-day test concluded in 1968. 



^hh 



Appendix A 
SSS CREW TRAINING CURRICULUM 

INDEX 



Biomedical Procedures 

Microbiology 
Medical Monitoring 
Blood Sampling 
Urine Sampling 
Physical Fitness 
Experiments 

Life Support Systems 

Water Subsystems 
Atmosphere Control 
Mass Balance 

Man/System.s Integration and Operation 

Human Factors 
SSS Procedures 
Support Functions 
ExperimLents 



5i^5 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



Biomedical Procedures 

Microbiology 

To train crewmen to perform bacterial sampling and 
counting, and operate the experimental equipment 

1. Classroom 

A, Introduction 

B, Sampling and Counting 

C, Sterile Techniques 

D, Potable "Water Protocol 

E, Experiments 

2. Practice 

Each crewman will perform the sampling and 
counting operations using sterile techniques under 
the direction of the instructor. Several crewmen 
will be selected to specialize in experiment per- 
form.ance and bacteriological protocols 



CRITERIA FOR 
CERTIFICATION: 



Satisfactory demonstration of raanual techniques and 
knowledge of m.icrobiological methodology. 



3h6 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Biomedical Procedures 

Medical Monitoring 

To train crewmen in the correct application and use 
of monitoring equipment 

1. Classroom 

A, Introduction 

B, EKG Electrode Application 

C, Respiration Rate 

D, Body Weight 

E, Blood Pressure 

F, Oral Temperature 

2. Prac'ice 

Each crewman will practice each function under 
the supervision of the instructor. Several crew- 
men will be selected to specialize in these 
measurements 

Satisfactory perform.ance for each medical measurement 



5^7 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Biomedical Procedures 

Blood Sampling 

To train crewmen in safe and accurate sampling 
techniques and assessment 

1. Classroom 

A, Sampling Introduction 

B, Veni- Puncture Technique 

C, Blood Smear Procedure 

D, Hematocrit 

E, Vacutainer Preparation 

F, Hemoglobin Determination 

G, Waste Material Handling 

2. Practice 

Each crewman will practice each function under 
the supervision of the instructor. Several crew- 
naen will specialize in the sampling and analytical 
procedures 

Satisfactory performance for each procedure 



3h8 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 
COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Biomedical Procedures 

Urine Sampling 

To train crewmien to perform, accurate analysis 

1. Classroom. 

A. Voiding and Measurement 

B. Specific Gravity Determination 

C. Labstix Analysis 

D. Sample Preparation 

E. Waste Material Handling 

2. Practice 

Each crewman will perform each function under 
supervision. 



Satisfactory analysis, preparation, and sampling 
techniques denaonstrated for the instructor 



5^9 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Biomedical Procedures 

Physical Fitness 

To condition the crewmen to an acceptable level of 
physical condition 

1, Classroom 

A. Introduction 

B. Ergometer 

C. Treadmill 

D. MRM (paper no. 39 of this symposium) 

2, Practice 

Each crewman will exercise as directed by the 
instructor to achieve and maintain the specified 
level of physical conditioning 

Achievemient of prerun fitness baseline 



550 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Biomedical Procedures 

Biomedical Experinaents 

To train crewmen in the use and operation of the 
experimiental test equipment 

1, Classroom 

A. Silver Ion Generator (not used) 

B. Visual Tester 

C. Glycerol- Based Drink 

D. Spirometer 

2. Practice 

Each crewman will operate the equipment under 
the instructor's supervision. 

Acceptable performance on all items 



551 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Life Support Systems 

Water Subsystems 

To train the crew to operate and maintain the water 
subsystems so as to ensure their safety and collect 
meaningful data. 

1. Classroom 

A. Air Evaporator Unit 

B. Wash Water Unit 

C. VD-VF Unit 

D. Isotope Handling 

E. Potable Tank Procedures 

F. Multifiltration Unit 

G. Water Dispenser 
H. System Changeover 
I. Sanapling Protocol 

J. Contamination Procedure 

K, Backup Water 

L. Waste Management 

2. Practice 

Each crewman will practice startup, operation, 
and shutdown of all equipnaent. Several crewmen 
will be selected to specialize in life support 
systems operation and maintenance. 



Satisfactory denaonstration of equipnaent operations 
and maintenance 



552 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Life Support Systems 

Atmosphere Control 

To train the crew to operate and maintain the atmios- 
phere control systenas in a safe and efficient manner. 

1. Classroom 

A. Two- Gas Control Unit 

B. Thermal Control 

C. CO2 Concentrator 

D. Sabatier Reactor 

E. Toxin Burner 

F. Electrolysis Unit 

G. Atmosphere Particle Counter 

2. Practice 

Each crewman will practice startup, operation, 
and shutdown of all equipment. Several crewmen 
will be selected to specialize in life support 
systenas functions. 



Satisfactory demonstration of equipment operation 
and maintenance. 



353 



COURSE AREA: 
COURSE TITLE: 



Life Support Systems 
Mass Balance 



COURSE OBJECTIVE: To instruct the crewmen in the collection of meaningful 

data, the critical parameters, and expected values for 
all the data. 



COURSE OUTLINE: 



Classroom 

A. Engineering Monitoring 

B. Water Balance Analysis 

C. Data Management 

D. Crew Life Support Monitor 
Practice 



CRITERIA FOR 
CERTIFICATION: 



Class attendance and denaonstrations of knowledge of 
nnass balance fundamentals and data collection 



^^h 



COURSE AREA: 
COURSE TITLE: 



Man/Systems Integration and Operation 
Human Factors 



COURSE OBJECTIVE: To train crewmen in techniques and goals of the 

behavioral program 



COURSE OUTLINE: 



1, Classroom 

A. Cohesion Training 

B. Questionnaires and Tests 

C. Data Collection 

2. Practice 



CRITERIA FOR 
CERTIFICATION: 



Attendance and participation in classroom 



555 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Man/Systems Integration and Operation 

SSS Procedures 

To train crewmen in operation of simulator and living 
functions in a safe and efficient manner 

1. Classroom 

A. SSS Familiarization 

B. Pass-Through-Port Operation 

C. Lock Operation 

D. Contingency Procedures 

E. Food Management 

F. Oven Operation 

G. Housekeeping 
H. Recreation 

I. Hygiene 

J. Garbage Handling 

2. Practice 

Each crewman will perform all operations and 
participate in the contingency procedures. 



Attendance of lectures and participation in practice 
sessions. 



556 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Man/ Systems Integration and Operation 

Support Functions 

To instruct the crewmen in the concepts and method- 
ology of 90-day test goals, ground rules, and 
communication procedures 

1. Classroonti 

A. Time Share Comiputer Link 

B. Communications 

C. Ground Rules 

D. Mission Analysis 

2. Practice 
None 



Attendance at lectures and dem.onstrated grasp of 
support function concepts. 



557 



COURSE AREA: 
COURSE TITLE: 
COURSE OBJECTIVE: 

COURSE OUTLINE: 



CRITERIA FOR 
CERTIFICATION: 



Man/Systems Integration and Operation 

Man/Systems Experiments 

To operate the test and measurement devices and 
achieve asymptotic performance levels on the 
psychonnotor devices 

1. Classroom 

A. Light Measurements 

B. Psycho-Acoustic Measurenaents 

C. LRCCC 

D. Human Describing Function 

E. Rater 

2. Practice 

Each crewman will practice measurements and 
operate the psychomotor devices for the estab- 
lishment of performance baselines. 



Establishment of asymptotic performance levels and 
demonstrated proficiency in light and sound 
measurement 



558 



ID 
O 

on 
on 

ZD 

o 
o 



8 -• 9 o 

^ O ^ Qi 

OH ^ *= 

S z o o 

S o o o 

^ "^ ^ -^ 

•- ? 2 ^ 

Qs: a- ^ 3: 

O ^ >— •— 

a. S • • 



O 

Qi >< 

^ O _ 

o c^ >: 



CO 



o 
o 



!±1 o 

O CO LU 



CO 



^ CO <- 



CO 

O 
Cl 

o 
o 

< 

_j 

< 
C30 

CO 
CO 

< 



< 
LU 

o 
o 

< 



s § 

CO U_ 



CO 

>- 

CO 



CO 
UJ 
OH 

o 
uu 

o 
o 

OH 
Q. 

CO 
CO 
CO 



CO 

z 
o 



0^ 

o 
a. 

CO 



CO 



OH 
LU 

a. 

X 



-z. 






























LU 






























S 






























^ 






























tu 






























t^ 






























o 






























CO 






o 














Q^ 








z 


CO 


CO 




"Z. 












CO 


o 








o 


CO 


UJ 




OH 






CO 




CO 


s 


5 


OH 






\— 




^^1^ 




O 


o 


o 


CO 




s 


UJ 

1— 

CO 


o^ 


UJ 






< 




o 


>- 


h^ 


^ 




UJ 




Jj 


o 

ft 


5 




o 

Q. 

< 






UJ 

o 
o 

OH 
CL 

1 


o 

2 
o 

QQ 


o 
< 


< 
CO 


Zj 
Q. 

< 
CO 


u. 

—1 

s 


CO 
UJ 


CO 
CO 


>- 

CO 
CO 

CO 


< 
> 

UJ 
OH 


CO 

< 


U- 

> 

1 

o 


1 

i 

o 




wmU 

< 


O 


o 


UJ 




^ 


o 


OH 


< 


> 


CO 


o 




OH 
O 


o 


o 
o 




CO 

>- 


UJ 


a. 


UJ 


• 


• 


• 


• 


• 




o 

UJ 


S 


UJ 




^ 




UJ 


CO 














o 


• 


• 


• 


• 


• 


• 


UJ 

u_ 


• 














QQ 














-J 















559 



Table 2 
CREW PROFICIENCY RATING 

STUDENT INSTRUCTOR_ 



COURSE DATE COMPLETED 

Skill Level (Highly Skilled, Skilled, Semi-Skilled) 

Class Standing 

1 5 

2 . .. 6 

3 __^ 7. 

4. 8. 



Attitude (Enthusiastic, Attentive, Complacent) 

Remarks: Cover special aptitude for maintenance and repair, knowledge of 
operational procedures and system. 



560 



Table 3 
CREW COURSE RATING 

STUDENT INSTRUCTOR. 



COURSE ^ DATE COMPLETED. 



What skill level have you achieved through participation in this course: 
(Highly skilled, skilled, semi-skilled) 

How do you rate the class on skill level achieved? 
(Enter names of all crew members including yourself) 



1 5.. 

2 6.. 

3 7.. 

4 8.. 



How do you rate the performance of the instructor: 

Knowledge of subject Excellent, Good, Fair 

Delivery Excellent, Good, Fair 

Compatibility with class Excellent, Good, Fair 



Remarks: Include recommendations for future course improvement and 
indicate areas in which you would like additional review. 



361 











> 




































(9 




































O 




































-1 




































O 


Ul 
















13 


















M > 








c 
























o 

-1 


> 


i 

Ul 


>- 


> 

C9 


> 


Ul 

5 


&3 


> 

(9 


> 


z >- 


> 

(9 
















uT 

z 

u 




3 

o 

X 


3 
S 


3 


Z 

8 


z 


3 


o 


Ul o 

f 3 
< o 


















QOO 
Ul 2 Ul 


i 


> 


1 


Ul Ul 

Z 1- 


i 


M 




u 
















X 






























lU 
Ul 


Z 
















CO 

z 


















Ul 


















Ul 

Ul 


CO 

Z 
















O 


«» 




^ 


< 


^ 


S 




i 


1 


s' i 


i 


Ul 








> 




,^ 


























0^ 


O 
lU 


























O 

Z 

Ul 






o 


-1 


1- 


Ul 






























t— 


o < 


u 
























£ 






o 


z 


-i 


z 
























Ul 

a. 
IS 






oe: 


X 


m 

EC 


Ul 

£ 






o 


o> 


* 


IV 




'" 


at 


U> lO 


S 






1— 




O 


Ul 
























^ 




CO 


CO 


lU 
























§ 


s 


Ul 

z 

■J 


e> 

< 
1— 






























Z 

X 


Ul 


Q. 






3 

Ul 


1 


IS 

-1 

1 

Ul 

S 

Ul 


IS 

-1 

1 


3 

il 

Ul 
Ul 


3 

1 


3 

1 


>- 

§ 

o 

§ 

K 
U 

i 


> 

o 

3 
o 


RADIOLOGY AND 
MEDICAL PHYSICS 

MICROBIOLOGY 


Ul 
Ul 

o 

Z 
< 

Ul 

Z 

5 
2 


3 

CO 

K 

> 

z 
< 

z 


o 

Ul 

o 

s 

i 

< 


5 

i 

z 

X 

Ul 










Ul 

S 


X 
u 


Ul 

S, 


X 
u 


Ul 

S 


Ui 

Z 


£ 


Ul 

z 


§ 


CO 


a» 






























Q 










Ul 
Ul 






















Z 














oc 






















yj 














o 

Ul 

O 


S 


i 


S 


s 


|g 


S 


z 


Q 


^ 


i 


Ul 










is 


> 




























-J 


K- 


Ul 
































i 


< 

-1 


U 
































5S 


Ul 


CM 

1" 


00 


ID 


CO 


o 


"• 


N 


8 


i«» 


CM 


eo 










ill 


O 

z 
< 


£ 
































g 


Ul 
































CD 




Ul 































362 



BEHAVIORAL PROGRAM 
ByJ.S. Seeman and M. V. McLean 
McDonnell Douglas Astronautics Company 

SUMMARY 

The behavioral program assessed effects of confinement on crew 
behavior in the areas of psychological status^ sleep durations, and task per- 
formance. Psychological status and sleep durations were measured by objec- 
tive questionnaires. Task performance information was obtained by TV 
monitoring of the onboard crew. Psychologically, the test was not severely 
stressful as expected, but periods of low inorale and intiild hostility were noted. 
Certain tests appear somewhat insensitive and are candidates for exclusion 
from future studies. More subtle or sensitive tests must be developed in their 
stead. Sleep durations were significantly shorter during the early part of 
mission for crewmen on inverted sleep cycle and adaptation did not occur until 
approximately the mid point in the test. Task performance information indi- 
cates a relatively poor use of the crew in terms of work performance. 

BACKGROUND 



A great deal of research has recently been directed toward determining 
individual and group reactions to isolation and confinement. Findings common 
to most of these studies have included: manifestations of boredom and 
monotony, declines in morale, interpersonal problems, great individual self- 
control to contain hostilities, scapegoating on outside personnel, impairment 
of memory, and low energy for intellectual pursuits with little or no loss in 
intellectual ability. (For more detail in this area, see Appendix A. ) To the 
extent that one or more of these simiilar developments manifest themselves 
during an orbital or deep space mission, the efficiency and effectiveness of 
crew may be compromised. The research reported herein is oiie attempt to 
obviate such an occurrence. 



OBJECTIVE 



The objective of this sub-program was to assess the effects of confine- 
ment on crew behavior. 



365 



PROCEDURE 

During the 90-day test various tests were taken by the crew at scheduled 
times. The tests were self- administered and answered via an onboard 
computer keyboard. One category of test consisted of those which were 
considered to avail the outside staff of timely information concerning crew 
status and were available for real-time analysis. The other category consisted 
of tests that were available for post-test analysis only. Both categories are 
listed in Appendix B. Only group mean scores are reported. 

Task performance was determined by continuous TV monitoring and the 
logging of start and stop times for crew activities. This area is fully covered 
in the mission activity analysis (paper no. 2k of this symposium) and will not 
be detailed here. 

RESULTS 

All the resultant data show a great deal of consistency. Decreases in 
positive affect are generally supported by increases in negative affect. 
Plotting the primary affect scale (PAS) as a positive and negative dichotomy 
shows a clearly significant drop in positive affect that reaches a low on 
day 59 and increased moderately thereafter (fig. 1). This curve is generally 
followed by corresponding increases and decreases in the negative affect 
curve, A spike, however, in positive affect occurred on day 52 that is not 
supported by a corresponding decrease in negative affect. 

Subjective stress (plotted in the same figure) began with an initial high 
and then dropped to a very low level. A moderate rise occurred during 
days 45 through 75 which is in agreement with the PAS results. 

The isolation symptomatology questionnaire (ISQ) results are apparently 
less sensitive (no statistical tests have been applied yet) than PAS or the 
stress scale, but trends are still apparent in the graph. These data were 
dichotomized into positive and negative categories and the resulting plots show 
a slight downward trend in the positive factors. An upward fluctuation in the 
negative factors occurs about day 65, and is followed by a downward trend 
on day 85, The PAS, stress scale, and ISQ were combined into one plot as 
they all purport to measure individually oriented effects. 

The group confinement inventory (GCI) shows plots similar in trend and 
apparent sensitivity to the ISQ. The positive scale decreases moderately 
about the third quarter of the mission and subsequently rises during the last 
quarter. The negative scale shows a slight increase through the third quarter 
and then displays a plateau. 



36k 



Intercrew hostility, as measured by the hostility scale, peaked around 
day 16 (a result supported "by the stress scale) and decreased to a roiigh pla- 
teau hy day 50. Hostility directed toward outside personnel peeiked at day 32 
and decreased to approximate the intercrew hostility plateau "by day k^. GCI 
plots and the' two hostility scale plots are shown together as they are socially 
directed tests (fig. 2). 

The sleep data, in terms of variability and duration, indicate that crew- 
men 3 and 4 on the inverted sleep cycle did not achieve complete adaptation 

until nearly the middle of the test (fig. 5)- Group reported sleep time is 
shown in figure k. 

The descriptive sentence test did not indicate any deterioration in 
cognitive functioning. 

Task performance was divided into categories of: (1) operational tasks, 
(2) meals, (3) free timie, and (4) sleep. Sampling over 23 days (not always 
consecutive) revealed that 14 percent of crew time was spent on operational 
tasks, 9 percent on meals, 37 percent free time, and 37 percent on Sleep 
(see fig. 5 and table 1). Figure 5 shows an apparent trend in free time 
increase from naidpoint of the test until just beyond the two-thirds point when 
a reversal is noted. 

Hostility and stress measured on the outside personnel, i. e. , persons 

in contact with the crew, was very low level and showed no significant 
fluctuations. 

Appendix A supports the position that the 90-day test was an adequate 
simulation of an operational mission by providing indirect evidence that crew 
behavioral changes seen during the test were different only by degree from 
those seen under operational conditions. 

CONCLUSIONS 



The overall low-level scores in the negative test categories and the 
stress scale indicate that the test was not perceived as stressful by the crew. 
Whereas the mission may not have been stressful, neither was it a happy or 
pleasurable experience for the crewmen. 

Reported intercrew hostility w^as generally quite low, but isolated 
incidents were observed that were evidently not reflected in the hostility scale. 
This may have been an attempt by the crewmen to avoid negative references 
to one another. 



565 



All the data point to a definite slump in crew morale from approximately 
day 45 through day 75. This finding is supported by diary entries and outside 
observations. The spike in positive affect noted on day 52 PAS results is 
somewhat inexplicable but may be the result of: 

A. Completing the half-way point in the mission. 

B. Increased crew social interaction on that day. 

C. Highest crew mean sleep timie occurred in the sleep period 
immediately before the test. 

D. Spurious data not: supported by other tests. 

E. A real increase in positive affect for unknown reasons. 

Insofar as hostility toward the outside personnel was concerned, it was 
minimal and never became a problem. By the sam^e token, stress and 
hostility in the outside personnel was negligible and displayed no apparent 
relationship between the occurrence of stress or hostility onboard. 

Interestingly, there was more hostility shown toward the sound level in 
the equipment compartment than toward members of the study. Also the 
equipment compartm.ent sound level was measurably more annoying than that 
in the crew compartment. 

Certain behavioral tests (ISQ and GCI) may be insensitive to the low 
levels of stress inherent in the SSS. Unless additional information comes to 
light which denies this conclusion, these tests are prime candidates for 
elimination from future batteries. 

The suggestion that crewmen may have consciously biased behavioral 
test scores on at least the hostility scale (corroborated by post-test debrief- 
ings) indicates that the validity of these devices for assessing affect states of 
individual crewmen is highly suspect. This conclusion points out the desira- 
bility of increased effort to develop valid techniques for the measurement of 
affect states. 

The crew reported its primary difficulty resulting in boredoin was the 
inadequacy of the work program. This inadequacy resulted in an overall use 
of crewmen for approximately 1, 200 man-hours of work out of a total of 
8, 600 man-hours of time during which work could have been accomplished. 
This is an approximate 14 percent utilization of the crew for mission- related 
tasks. As time progressed during the test and as subsystem^ difficulties were 
resolved, free time available to crewmen increased and work-related activities 
decreased (fig. 4). This is probably not unlike what wo\ild be expected on 
an actual mission in terms of utilization of time by crewmen over the mission 
duration. A point to be made here is that almost without exception all crew- 
men felt that more could have been accomplished in terms of work perform- 
ance on board had there been more to accomplish. As with inost group 



%G 



confinement studies, inactivity or free time not devoted to productive 
mission-related work may be considered anathema and the primary problem 
to overcome in successfully scheduling activities of crewmen for long-duration 
confinement situations. 

During debriefings the crew expressed a desire for more responsibility 
to reside onboard in running the mission. This is particularly true in regard 
to the role of the Crew Commander. The role of the Crew Commander 
apparently was not satisfactorily defined before the mission. Consequently, 
the Crew Commander was uncertain about his responsibilities and authority 
on-board. This uncertainty affected his effectiveness to no small extent. 

Behavioral restdts are considered sufficiently accurate to be employed 
in the prediction of human behavior under operational mission conditions. 
This conclusion is based upon the findings reported in Appendix A. 

Unfortunately, the minimal behavioral effects noted during this 90-day 
test do not provide sufficient information to permit extrapolation to missions 
of greater duration. Similarly, information based upon a group of four pro- 
vides little data for the prediction of behavior of groups consisting of more 
than four crewmen. 



567 



Appendix A 
MISSION SIMULATION FIDELITY 



In a recent review of the effects of confinement and isolation upon small 
groups. Smith''' reports the following findings relevant to our study; "'In con- 
trast with findings from studies of individuals isolated alone, groups in 
confinement report far fewer unusual sensory experiences, perceptual distor- 
tions, unusual dreaons, and etc. Confined groups, however, often face very 
difficult inter-personal problems, and particularly in lengthy confinement, 
may experience tedious boredom due to the unchanging environment." 

A. "As well documented as any finding in the group confinement litera- 
ture is sizeable presence of irritability, hostility, and personality 
conflicts, although often, to avoid alienation of the group, persons 
made great efforts towards self control (sic). These inter -personal 
problems have been shown to be more serious among groups, who, 
by personality composition, could be expected to be incompatible. 
Highlighting the importance of group compatibility for confinement, 
incompatible groups are also under more stress and report more 
symptomatology than do compatible groupings. Members of con- 
fined groups tend to withdraw from one another and from group 
activities more and more as lengthy confinement drags on. They 
also display increased territoriality for areas and for positions, 
perhaps in their quest for privacy." 

B. "Relationships with those outside of confinement are subject to 
change as well. Much of the aggressive hostility that is observed 
is frequently directed away from the group, perhaps representing 
useful scapegoating. There is speculation that the loss of meaning- 
ful and relevant feedback from the parent society may be a problem, 
particularly in very lengthy and isolated confinement." 

C. "There are several reactions to group confinement that are fre- 
quently stated. In lengthy confinement, boredom and monotony are 
characteristically mentioned even when facilities are available to 
alleviate the problem. For some groups morale and general 
motivation remain at acceptable levels, but pronounced declines 
are frequently in evidence and there are no reported instances of 
consistent morale increases over time." 

D. "Many things serve to annoy members of confined groups. Thfese 
annoyances frequently center around crowded conditions, inter- 
personal problems, food, difficulties of maintaining cleanliness, 
ajid environmental factors such as noise and odors." 



Smith, Seward, Studies of Small Groups in Confinement, in Sensory Deprivation: 
Fifteen Years of Research; Zubeck (ed. ) Appleton- Century-Crofts, H.Y. I969 

368 



E. "Most of the reported symptomatology focuses on sleeplessness, 
depression, general mood declines, compulsive behavior and 
psychosomatic problems. It appears as if holding back overt 
expression of irritation and hostility leads to frequent instances of 
headaches and other psychosomatic complaints." 

F. "Performance measures have been employed in many studies. As 
a rule, neither intellectual effectiveness nor perceptual-motor 
ability shows any consistent change of note dtiring short-termi con- 
finement. The picture is not so clear for very lengthy durations, 
such as is characteristic of wintering over in the Antarctic. 
Impairment of memory, difficulty in concentrating, low energy 
for intellecttial pursuit, and less team performance effectiveness 
are often reported. So far test data are lacking to substantiate 
many of these feelings." 

The final test of the adequacy of mission simulation seems to be the 
degree to which phenomena usually found under conditions of confinement have 
occurred during the mission in question. The phenomena reported below 
derive from debriefings and observations accomplished during the test. Com- 
paring the findings concerning our test crew with findings of Smith's review, 
we see the following corresponding similarities and differences: 

A. Only one crewman reported unusual dreams. Another crewman 
reported an isolated incident of an apparent perceptual distortion 
in which he reportedly saw things out of the corner of his eye which 
were not really there. This may have been related to that particular 
crewman's level of fatigue at that moment. Three out of four crew- 
men reported problems with boredom due to the unchanging environ- 
ment, especially as the two- thirds point of the mission approached. 

B. Although irritability, interpersonal hostility, and personality 
conflicts did occur during our mission, they could not be described 
as sizable. Most crewmen, reported making great efforts toward 
self control. This self control was referred to by the crewmen as 
an attitude of professionalism. If interpersonal problems are more 
serious among groups who by personality coinposition could be 
expected to be incompatible, then there is no other alternative than 
to conclude that incompatability among personality characteristics 
of our crew members was minimal. Throughout the mission the 
crew tended to withdraw from one another. At times, interactions 
were not existent; even with concurrent physical proximity. Some 
evidence exists that territoriality for areas, in our case subsystems, 
and for possessions took place. This was not a prominent aspect of 
the mission. 



569 



C. Though unreported by communication monitors, principal investi- 
gators, or others who came into audio contact with the crew, 
post-test findings reveal that some communication monitors were 
used by some crewmen as scapegoats for hostilities. Although not 
a prominent feature of the relationship between onboard crew and 
the outside crew the fact remains that these incidents were reported 
by the crewmen. 

D. Although general motivation of the Crew remained at an acceptable 
level, a trend toward decline was in evidence through the two- thirds 
point in our mission when' a reversal apparently took place. Only 
one data point of the many taken through the mission supports the 
conclusion that morale may have improved at any time during the 
mission. This was at the day 52 point and is discussed in the 
behavioral findings as a possible elevation in affect as a consequence 
of having accomplished 50 percent of the mission. Otherwise, mood 
generally declined. 

E. Crowded conditions, food, and environmental factors such as noise 
and odors were not a prominent source of annoyance for the crew. 
Difficulties in interpersonal relationships and in maintaining body 
cleanliness were mentioned after the test. Never was the annoyance 
at such a level that crewmen felt obliged to express their annoyance 
to program management personnel. 

F. On a group basis, sleeplessness, depression, compulsive behavior, 
and psychosomatic problems were not characteristic of this crew. 
Individual crewmen did display occasional behavior indicative of 
depression, compulsivity, and psychosomatic problems. If the 
holding back of overt expressions of irrationality and hostility leads 
to increased frequencies of complaints, then we are left with the 
conclusion that the degree of such withholding of expression, as a 
consequence of the overall degree of irritation, was minor. 

G. Performance measures employed during the test displayed no con- 
sistent deterioration. The one performance measure (LRC-CC) 
employed by all four crewmen throughout the 90 days, three times 
a day for 100 trials each time, showed a continuous learning curve. 
Two crewmen report a decreasing desire to engage in intellectual 
pursuits over time, one reported impairments of memory and 
thought. None reported significant difficulties in concentration, 
but the impression of team performance effectiveness deteriorating 
over time is substantiated by post-test reports. 



570 



Appendix B 

TEST USED 

The following tests avilable in real time: 

A. Hostility Tests - measures mood on a continuum from pleasure to 
hostility 

1. Inter/onboard crew 

2. Inter /outside personnel 

3. Toward outside personnel 

4. Toward onboard personnel 

5. Toward acoustic environments in crew and equipment 
departments 

B. Subjective Stress Scale - measures subjectively perceived stress 
on a continuum from none to incapacitating. 

1. Onboard crew 

2. Outside personnel 

C. Descriptive Sentence Test - assesses cognitive functioning 
(reasoning). Onboard crew. 

D. Sociometry - assesses changes in sociometric preferences 
(group structure). Onboard crew. 

E. Sleep Questionnaire - assesses quantitative aspects of sleep. 
Onboard crew. 

The following tests available post test: 

A. Isolation Symptomatology Questionnaire - assesses effects of 
confinement on the individual. Onboard crew. 

B. Group Confinem.ent Inventory - assesses effects of confinement on 
the individual as he relates to the group. Onboard crew. 

C. Primary Affect Scale - assesses qualitative aspects of affect or 
feelings. Onboard crew. 



571 



CO 



< 

> 

>- 
< 
o 
I 
C3 
O 



LU 




_i 




CQ CO 




< Ol 




—J :3 


C3 


> 1 


^T 


vO 


< z 


OO 


-J < 




?s 




o 




H- 




o 5 


CO 


>- 



OQ 
< 



I 



< 
M 






O 
Q- 



^^ 


O 


OO Qi 


CD 


s^ 


O^ 


>- 




tl 


>- 


__i 


< 


QQ 


o 


< 


ai 


_J 


JO 






< 


•^ 


> 


CM 


< 




LU 




M 




___ 




t/) 




^ 


"ST 



LU ^ 














o o 




























J^ ^ 


■^^ 


O^ 


r- 


1*^ 


m 


o 


o^ — 


.»— • 




pn 


c^ 




^ 


Q- 5 












1— 1 


Z >- 














< -" 










































2 














^F 














>_ >— 














_1 UJ 














DAI 
ITUR 


'd- 


1— 1 


o 


OO 


OO 


o 


• 


• 


• 


• 


• 


• 


cr\ 


CM 


c» 


OO 


o 


'SI- 














CM 


X 














LU 















o 



















CO 
















Ol Q 
















3 LU 
















s§ 


'ST 
CM 


i« 


s 


OO 




§8 


o 

'ST 


1 l^ 


CM 


1^ 


CM 


1— 1 




CM 


vO 


2 CL 


1— T 




m 


crT 






oo" 


S^ 


















CO 








O 








^m£: 








2 








CO 








< 






ATION 
30RY 


< 

—J 

< 








CO 

O 

LU 


i 


_J 


M LU 


z 








z 




< 


Till 
CAT 


o 

1— 

< 


CO 




Q- 


-J 

LU 


O 

o 


^ 


=D 


ty 


—1 




o c_> 






LU 


< 


LU 
LU 


LU 
LU 


CO < 






Q- 


LU 


^ 


Zj 


■^ 


z^ 






O 


S 


U- 


CO 


S 


^ 





572 



O PRIMARY AFFECT SCALE POSITIVE FACTORS 

A ISOLATION SYMPTOMATOLOGY QUESTIONNAIRE POSITIVE FACTORS 

A ISOLATION SYMPTOMATOLOGY QUESTIONNAIRE NEGATIVE FACTORS 

• SUBJECTIVE STRESS SCALE 

D PRIMARY AFFECT SCALE NEGATIVE FACTORS 




40 50 

TEST DAY 



Figure 1.- Trends in personally oriented affect. 



100 



80 



60 



40 



20' 



(D A GROUP CONFINEMENT INVENTORY POSITIVE FACTORS 
(t) O GROUP CONFINEMENT INVENTORY NEGATIVE FACTORS 
® D HOSTILITY SCALE - TOWARD FELLOW ONBOARD CREW MEMBERS 

f« HOSTILITY SCALE -TOWARD OUTSIDE SUPPORT CREW 
O SOCIOMETRIC QUESTIONNAIRE 




^. 



X 



i- ^sr^ 



"^ 



:^^ 



©1/ 
(fi)i5 



/. 



•B 



■tr-. 



r^ 



(Dq- 



70 



20 10 20 30 40 50 60 

TEST DAY 

Figure 2.- Trends in group oriented affect. 



90 



575 



10 

i 9 
















































^ 






_ 








^— 






■~— 


== 


"vl 








^ 






1 








S^ 






1 


>^ 


y 


y 


y 






















s 








II 


/ 


































UJ 

S 6 




1 = CREWMEN 1 AND 2 (UNALTERED CIRCADIAN RHYTHM) 
II • CREWMEN 3 AND 4 (ALTERED CIRCADIAN RHYTHM) 


- 
















5 


































] 


5 













45 




60 




75 






90 



TEST DAY 



Figure 3.- Sleep questionnaire responses. (Smoothed curve 
based on 15-day segments.) 




1 5 10 15 20 S 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST DAY 

Figure 4.- Reported sleep time. 



y\h 



20 

UJ 

S 15 

1— 
z 
<: 

UJ 

^10 




MEALTIME M-aiHR 
Slf EP TIME M ■ 8.8 tt* 




UNSCHEDULED ENGINEERING ACTIVITIES M • 1.3 HR 



r*''*T^ I III I J ' ' 



5 10 15 20 » 30 35 40 45 50 55 60 65 70 75 80 85 90 

TEST QM 

Figure 5.- Crew time utilization (23 selected test days only). 



375 



MAlfflED KESSION ACTIVITr MM.YSIS 

Ety Karen Brender 
NASA Langley Research Center 

Edward R, Regis 
McDonnell Douglas Astronautics Compemy 



SUMMAET 

The objectives of the Mission Activity Analysis (MAfi.) experiment on the 
90-day test were to generate manual and coraputer schedules of planned crew 
activities for the purposes of 

(1) Evaluating the planning and scheduling capabilities of the LRC Space 

Station Mission Simulation Mathesaatical Model (SSMM) 

(2) Comparing crew performance data with manvial and computer-generated 

crew activity schedules 

The experiment ohjectives were succesSftilly accomplished. The MAA experi- 
ment crew event descriptions and scheduling activity acted as a forcing function 
for the early identification of problem areas and operational constraints. 

The MAA crew activity schedule provided direct and material support to the 
successful operations conducted during the test. 



INTRODUCTION 

The exitensive manual planning effort exjiended on space flights has been 
most effective as evidenced by the success of missions to date. However, the 
Increased emphasis on spacecraft utility, coupled with Increased mission com- 
plexity, crew size, and the pressing requirement for early selection of the 
most cost effective system to insure completion of the maximum number of mis- 
sion objectires, has resulted in the design of a number of planning and simula- 
tion computer models to support program planners. One such model, the Langley 
Space Station Mission Simulation Mathematical Model (SSMM), is an integrated 
set of 11 computer programs which provides the capability for in-depth space 
station program planning (fig. l). The many interrelated space station ele- 
ments, such as crew skills, human factors, station capabilities, experiment 
programs, and station operations and logistics, are considered in their proper 
perspective and the interactiaag effects of these variables are analyzed with 
respect to their effectiveness on the total lalssioni The 90-day manned test of 
a Regenerative Life Support ^stem with the McDonnell Douglas Space Station 
Simulator (SSS) as the space vehicle provided an excellent opportunity to eval- 
uate the planning and schedtillng capabilities of the SSMM and to compare actixal 
crew performance data with manual and computer.-generated crew activity schedules, 

577 




PROGRAM IJESCKEPTION 



Mission Activity Analysis was accomplished through mutTially supporting but 
independent efforts; McDonnell Douglas Astronautics Company (MDAC) employed 
manual planning and scheduling techniques and computer schedules were generated 
at Langley. Although it will be possible to cover only the more significant 
areas required for the accomplishment of this effort, it is considered of some 
importance that they be presented in sequence to provide a better understanding 
of "mutually supporting but independent efforts." 

Definition of Data Submittal 'ffarm.t 

mc designed the data submittal format for the crew skill matrix (table I) 
and crew events matrix (table II ) to ensure that all essential data items were 
provided for adequate exercise of the planning and scheduling capability of the 
SaSM. !Ehe formats were coordinated with MDAC to ensu^re that they would allow 
the inclusion of all test and operational constraints and provide an easily 
understood and usable method of presenting the data. 

i 

Collection and Formatting of Crew Events Eteita 

The initial colledticMa and f oi^matting of the crew events data was acccan- 
plished by MDAC by using the traditional methods required during the initial 
planning stage of any program, by analyzing system and experiment descriptions, 
and by Interviewing engineers and essperimenters. At the time of the initial 
effort, final selection of all systems and e3cp6riments had not been made. 
Therefore, the first iteration of the crew events matrix described only 
50 events, some incompletely and all with conservative time estimates. There 
were three major revisions to the matrix which reflected the inclusion of 
refined data with retention of the conseirative time estimates. The final 
iteration resulted in 87 events. The crew events matrix constituted a standard 
data base used by both liRC and MDAC far computer and manual planning and crew 
activity scheduling. 

Fornrulation. of Mission Event Profile 

In the initial scheduling effort, crew activities for the entire 90 days 
were set tip on a day-by-day basis to formulate the mission events profile shown 
in table ni. This profile was generated at the LRC by tising the Planning Model 
Routine of the SSMM (fig. 1) to indicate the events which were to be active on 
each mission day. 

The generation of this profile by the computer model provided a basis on 
which to evalTiate the model capability for long-teim scheduling. It also elimi- 
nated the need to spend the extensive time required to maiiually generate the 
mission events profile. This schedule was updated by MDAC as events were added 
to or deleted from the crew events matrix and it was the key document, when sup- 
plemented by details in the crew events matrix, used in crew activity 
scheduling. 

378 



formulation of Crew Activity Schedules 

Crew activity schedules, consisting of 270 pages of 8-hour mission seg- 
ments, were formulated on an Independent "basis "by LRC and JMMC with the fol- 
lowing items as standards : (l) mission events profile> (2) crew eyents matrix, 
(3) mission rules, (k) crew operating ground rules, and (5) given work/rest 
cycles for each, crewman (figs. 2 and 3). The work-rest doctrine of two up and 
two down was selected to ensure crew safety and provide the "best coverage of 
development-type EC/LS (environmental control/life support) eq.uipment. Allow- 
ance was also made, as much as practical, for crew preferences in the .ordering 
of tasks. The primary guide used for the MAA schedxxling effort was to provide 
for flexibility in performance of vuascheduled tasks without the necessity for 
disrupting the normal schedule. The crew activity schedules were intended as a 
guide and reference for necessary tasks to he conducted. 'She crew was at liherty 
to deviate from these schedules for any "non-time-critical" event . 

The manual formulation and subsequent revision; of schedules was a difficult 
and time-consuming task. Each of the three major updates of the crew events 
matrix contained numerous changes which necessitated a major update of the mis- 
sion events profile and a complete revision of the crew activity schedule. The 
large man ho-ur effort req_uired in this activity indicated the necessity for good 
planning and scheduling aids. 

The SSiViM formulation of crew activity schedules at LRC essentially paral- 
leled the manual effort . The initial haseline case for computer scheduling in 
which all activity, system, and crew parameters were formatted for computer 
input was the largest single step in the Langley effort. The first schedules 
produced hy the model necessitated a revision of model output into a more 
readily usable format and pointed up some problem; areas in the methods for 
handling the operational constraints involved. The problems were largely 
solved by the xise of the SSMM capabilities for setting up fixed times, priority 
assignments, (lamnon equipment checks, and predecessor-successor event chains 
and by a program, revision of plotted output. This resulted in a well-seq.uenced 
schedule in a format acceptable to operationally oriented personnel. 

Computer schedules were periodically updated to evaluate the SMI cap- 
ability for rapid generation of new schedules. Before test start, these itera- 
tions were based on updated events Information caatained from revisions of the 
crew events matrix. During the test, activity changes were based on interviews 
with the Crew Commander and analysis of dally monitor logs. Crew activity 
schedules for days 3I through 50 were provided to MDAC by Langley. Iterations 
and reissue of computer schedules was, on an average, more than one order of 
magnitude faster than the same changes made by manual methods. 

Training 

The Mission Analysis Activity training consisted of 1 hour for all crew 
members during which the purpose of MM was discussed in detail. An additional 
2 hours were spent in review of the 90-day crew activity schedule during which 
the crew verified crew constraints for scheduling a body /wash after exercise, a 
shave before breakfast , a free time period in conjunction with dinners , and. a 

379 



Tn^^^^TmTm of 1-liour time lapse between meals and exercise. During the 5-^7 man- 
ned test and during the first 15 days of the 90-day manned test, the MAA moni- 
tors received on-the-jot training. iDastruction was given to each crewman 
during an early duty shift to ensure he understood the written instructions for 
monitoring, logging of data, and operation of the time-lapse video system. 

Test Monitoring 

Data for this experiment were collected for days 51 through 60. The four 
"backup crewmen performed duty as MAA monitors. Continuous surveillance of the 
crew was maintained hy means of closed-circuit television monitors. A log entiy 
was made to record the start and stop time of each event and a time-lapse video 
system was used to record a picture each 5 seconds from one of five cameras 
within the simulator. The MAA monitor was assisted hy the communications 
monitor. 



Data Analysis and Report 

Data analysis is presently in process and therefore only preliminary 
results are presented in this paper. For each of the 10 test days selected for 
comparison, a de-tailed analysis was made of the mission analysis monitor's log 
to construct a graphic presentation of actual crew performance (fig. h) . The 
log information was supplemented lay review of video time-lapse recordings, on- 
hoard diaiy entries, and n033inte3rferende performance data. This information 
was then loaded for ccraputer program mianipulation to provide a listing hy day 
for each crewman of total scheduled time, total free time, total time for 
unscheduled engineering events, and total time for unscheduled nonengineering 
events. An analysis of each event performed showed the delta of starting time 
as a function of scheduled starting times for each. A summary of these data 
for days 51 and k^ (Mondays) is presented in the following tahl^: 



Ifey 


MDAC schedule 


Actual crew time, hr:min 


Computer 
schedule 


Scheduled 
time, 
hrrmin 


Free 
time, 
hrjmln 


Scheduled 


Unscheduled 


Epee 


Scheduled 

time, 
hr:min 


Free 
time, 
hr:min 


51 


62 'M 
64:45 


55:15 
51:15 


54:51 
58:51 


5:49 
7:10 


55:40 
50:19 


6lr05 
67:15 


54:55 
28:45 



The three basic elements of the tahle are defined as follows: 

(l) Scheduled events include haseline medical and manned systems events, 
station operations events, scheduled maintenance of SSS and experiment equip- 
ment, meals, sleep, experiment events, and personal hygiene (shave and "body 
wash only). 

580 



(2) Unscheduled events include unscheduled maintenance and repair of SSS 
and experiment equipment, crew response to staff requests for monitor or 
adjustment of equipment, interviews, and unscheduled medical events. 

(5) Free time in the MMC and computer schedules is the time for recrea- 
tion and all unscheduled events; in the crew performance schedule it is the 
time for recreation. 

Comparison of the manual schedule times and performance times in the table 
shows that on day 5I the crew spent 8 hours and ik minutes less on scheduled 
events than planned (approximately 2 hovirs per man). Of this time, 5 hours and 
^9 minutes were spent on performance of unscheduled events and the remainder on 
free time. The time used for unschedioled events and the increased free time 
period resulted from a reduction in scheduled event tlm.e rather than from a 
reduction of free time as originally envisioned by planners. This, is due partly 
because the schedule event times were conservative estimates and partly because 
of the crew decision to reduce scheduled event times to allow for necessary 
unschedtiled engineering tasks. For example, on day 31 approximately 48 percent 
of the time saved resulted from a reduction in xxse of time scheduled for meals, 
10 percent of time saved from scheduled exercise events, and the remainder of 
k2 percent from all other events. On day k^, the percentages are 70 percent, 
12 percent, and 18 percent, respectively. Most of the differences result 
frcm the time used for meals on each of the 2 days. The majority of the esti- 
mated times allocated in events were, in fact, fairly accurate. During this 
phase of the mission, the crew by choice limited time for meals when in their 
opinion it was important to spend the time in pursxiit of more productive matters. 
Aq event-by-event coniparison to establish specific reasons for differences 
between schedules and crew perf oomance is yet to be conipleted for the remaining 
8 days of the 10 selected for comparison. 

Figure 5 shows a plot of the average hours per crewman in each of the pre- 
viously mentioned categories of scheduled events, free time, and unscheduled 
events. It can be seen from this figure that differences between the activities 
scheduled and actixal work time are relatively small.. The free time spent on 
unscheduled engineering tasks, such as equipment repair, accoxxnts for most of 
this difference. The detailed ana,lysis of all 10 days will show exactly where 
the crew time for unscheduled inaintenance was acquired. Analyses of this type 
are also extremely usefiil as a cross-check of selected basic engineering data. 
For example, in the 10 days shown in this figure, the available time per day 
per man utilized for unschedtiled eqiilpment maintenance was I.5 hours. This 
average includes 2 d^iys (32 and 33) of heavy maintenance requirements, and cor- 
relation of the MAA data with engineering data on vacu-um- distillation— vapor- 
filtration boiler replacement confirmed this fact. 



CONGL0SIOIS 



The Mission Activity Analysis objectives of evaluating the planning and 
scheduling capabilities of the SSMM and of providing scheduling support to the 
90-day manned test were successfully met. Qjhe Planning Model's mission event 

381 



profile accurately reflected the requirements and constraints contained In the 
crev events matrix and -was one of the key tools used in manual plajinlng and 
formulation of the daily crew activity schedule. The mission. simulation model 
successfully sequenced daily events into crev activity schedules that were 
operationally acceptahle. The rapid generation of new schedules "by the SSMM 
during the test proved its capability to update as needed. For example, a 
response to an operational request to delay sleep start times . for crewmen 5 a-nd 
k for 1 hour demonstrated the model's capability to support a real-time request 
in that dally crew activity schedules for a J-day period were run and recom- 
mendations returned to the Test Program Director within 2k hours. Some desir- 
able modifications, such as faster input capability and improved methods for 
handling operational constraints, to fiurfcher increase ajid improve model capa- 
bilities have been identified as a result of the experiment. 

The LRC designed data submittal format for the crew events matrix requires 
operational personnel to perform a paartial task analysis of all events in which 
the crew will particijiate and further requires an ear3y definition of mission 
constraints. It provides a requirement for operational personnel to describe 
in their ovm language the input data and c^erational constraints necessary for 
crew activity scheduling by manual methods, or by use of the SSMM. 

The manpower and time allocated for data collection and foimattlng of crew 
events data were inadequate for a development-type test in which change is 
required up to test start to maximize the number of test objectives that can be 
met. 

Neither the time-lapse video tape nor the MAA monitor's log was adequate 
for recording data and the use of the two together was marginally adequate for 
this escperiment. The time- lapse system can record only one area of the chamber 
at a time and crew event identification is frequently difficult. An 8-hour 
shift for MAA monitors was too long a period of time for the monitors to pro- 
vide continuous attention to crew activity. Numeroixs errors were noted in the 
mamxal logs after the fifth hour of shift duty. Also, the monitor could not 
effectively observe and log the activities when all four crewilen were up at one 
time. The diversity of activities in different areas of the simulator did not 
permit total coverage. 

RECKapEamATIONS 



The IBC designed data subniittal format for the crew activities matrix 
should be eraplc^ed in any fature manned simulation tests. Further, it should 
be considered for use in crew activity scheduling for manned flights since it 
Serves as a forcing function to perform a detailed analysis of crew activities 
and provides for the early definition of missioii constraints. 

Any futui^ manned development test should provide for a task analysis early 
in the program to insure realistic event time estimates^ crew procediires, and, 
equally ±Bg)ortaat, a means of Identifying those key factors in crew events which 
can be used as a measure of performance. 

382 



Although the schedules used were acc^table, on future manned jnissions of 
longer duration with dynamic experiment programs a more easily handled crew 
activities schedule should he provided to he used in conjunction with a capa- 
hility for updating onhoard schedules on an as-needed hasis to eliminate the 
necessity for prescheduling the entire missicai. 

Prior to future manned tests, a study effort should be conducted to define 
a more effective method for monitoring eind logging of crew activities. 

Manual and Space Station Model activity schedules were "both operationally 
acceptable in event sequencing for the 90-day test. Since the computer has a 
marked advantage in the time required to generate and update activity schedules, 
future manned tests should tise, -whenever possible, conrputer-generated crew 
activity schedules which have been reviewed and approved. 

It is most iBDportant that the present philosophy be maintained! that is, 
the crew activity schedule is a management tool and should provide as much 
flexibility as possible to permit continuous attention to unscheduled require- 
ments without disruption of the remaining schedule for the day. 



585 



TAHiE I.- CREW SKEII. MAIRIX 



Skill 


Crewman 


1 


2 


3 


It 


Mechanics 


2 


2 


1 


1 


Electrical/electronics 


2 


1 


2 


1 


MLcro'biology 


1 


1 


2 


2 


Biochemi stry 


1 


1 


2 


2 


Medical treatment 


2 


2 


2 


2 


Photography 


1 


1 


1 


1 


utn-rty 


1 


1 


1 


1 


Special, requires crewman. 1 


1 











Special; requires crewman 2 





1 








Special, requires crewman 5 








1 





Special, requires crewman k 











1 



Notation: 

1 Primary sMll 

2 Secondary skill 
No skill 



38k 



ta 



I 

o ai 
^s 

a s 

fl o 

u 

CQ a 
la 
d 
p, 

o o 
J) +J 

£ f< 
^ o 



^8' 




+1 <u ^ 

(u 0) u a I 
H p< (a aj iM 

-■ ■ +> CT\ a! 

a K n 



•a 



CQ 



^ OJ 
U 0) 






8 

vo 



■P o 
13 -H 

a) -p 

« +> 
O in 



s 

(U o 
F4.ia 



n 



m 

^ 






■P -P 



I 
■P 



o 



la 



s 



§ 



I 

I 



« 

4 







•P 



I 



1 



A. 



11 






© 






385 



_j 

U- 

o 
q: 

Ol 

(/) 
h- 

z 

LLi 
> 

UJ 

z 
g 

</) 
w 



m 



• • " »••• 


-: ::--••!. 


t s _ ••••_^ 


: •••• 




•••• •••• 


,_i_.i •itSIII 


• •• ( • 


,_•_, _ __ _ __ •§• 


» _ -_•••» 




• 


: :i::::::::::iiii;;: 




. :i::i;:_:,:^iisii:_ 




111 ^ :':§!•• 




S 1 • •••••••• 


•••• 


|:»:"::::::::8SSi::: 








'M • 


• 


s:i::i::::::: iiii::: 




2_s -^ -^ "•ls_ 




S -• • 'S^^ 




S ' • • j •• >••• 


• ••• 


S S • i • •! 


• 


^ J 




^ • 


• • 


!l_a«Z__ 5'is 


• 


i:a::i:::::::isii::: 


• 


1 •: I ^:i«i« 


• _ _ _ _ 


S • • _«««i««S« 


• ••0 


3 • iaa • 




3 • 5 _ ••• 


t 


s # 


• 


3 • • •••« 




3 _s_ _ _ ••§« _ 




S • • •• • • 




• SZiiSSa* 


• • • • 


• • ~ SiS* 


• 








• • 


• •••• 


• 


• • • ••• 


• 


• •••• 


• 


M. • • ••••■••• 


• • • • 


;S • aSii 




j« * * 






_- ._ 


• • ■••• 




• i • •• 




5- • • •*•• 






. ....ssss. .ssss 






S • 


._ iiii 


S • V 


• • •••• 


S_5 •••• 


• •••• 


s • • •••• 


-__ 


3 • • ••• 


• 


S • 'i •••••••• 


• ••• 


& * •••• 




is * * *** 


• 


n * 


• 


s • • •••• 




»_• '••• 




1 • • •••• 




1 • •••••••• 


• ••• 


S"S""i- aSii 


• 


1 * 




3 • • 


• ^ i 


3 • aS** 


• 


R • • ••• • 


• 


s • •••• 


• 


s. • • •••••••• 


• ••• 


2"i •••• 




M tt # 




^ • 


• 


si • •••• 




S_s _!•••_ _ 




l:s::i ::::_:*•«•:_: 




s • •••••••• 


_ ________ 


^_____ 5»ii~ " 


• 






j£_«__i 


• • 


^_$ . •••• 


• 


liiiii ::::: iiii::: 


__• 


s • •••• 


8 


= • • •••••••• 


• ••• 


J i iSii 




• • • ••• 


• " •••5 


m • 


• •••• 


-"•""• •••• 


: ":_:":: :_::iii« 


"_• •••• 


• iii 


' 1- s •••• 


• ••• 


w • ••••■•$• 


•••• iiai 


" • ••••_ 


_ - ii»i 


- , : — ~ 


■■■■■■HHBUHHMHHBBDDDn 



annsnnociHnnnDCBcaciBncanBnnnBncEnHnaHaoEDBtaan 






1^ 

BBS 



I 
,1 



-1 
iii 



gl 



I 
il 



s_ 



III 






ii^i 



IS 

m m 



386 









^ 


m^t^^ 




S! 




X 


ff 




oe 




Ul 




* 


s 




u 


^ 


^^, 


< 


i 


Ik 


a 

Ul 


^ o 




^ 


III 


i* 


§ 


2 


o 
< 


s 




S 


K 


k 


s 




• 


• 


• 


• 





Ul 








«J 


K 








> ua 


3 








S o 


^ 


•• 






IS 


< 
lb 


s 


H 


ca 


§§i 


8 


1- 

CE 


^^ 


Ss 


(= > 


Ul 




r" CJ 


OB B 


« 2 




2 


& = 




^ 


ce 


tn Ul 


^i 


• 


• 


• 


• 













c 






ill 






Z 


ae 


o Z 


K 




* S 


K 


K 


u S 


lU 


U 








g£ 




a 


ii 


o o 
u u 


ii 
IS 




• 


• 



ii 



<ia 



S K M u. 

_ I- X Ul 

Ul Z K 

Ul s u< — 

K is Z 

s OC = Ul 

S £3 I; 

• • • 



0) 

o 

a 

0) 

c» 

O 

I 



ci 
-t-> 

Qi 
O 

O 

o 



^« 


T3 


»- K 


O 


ssg 


n 


H- n = 




SsjS 


y 


INDI 

> MOO 

THIS 


« 
J 


T 


T-! 




0) 




^ 




a 




•iH 




fx< 



387 




388 




1-H 
-§ 

Qi 
X! 
O 
133 

O 

a 

u 
o 

t 

B 
o 
u 

m 
§ 
Q 



CO 



389 




I— I 

o 

03 
0) 

o 

d 

B 
o 
a 

ifi 

§ 
Q 






590 







^ 



<rs 




^ 




CM 


ca 


■«5f 


•iH 




>^ 






t—t 


g 


"^> 


rt 


< 


0) 


. Q 


1— *• 




-e 


1— 


5i 


CO 


X) 


k ixJ 


o 


in«- 


m 


m 


t» 




-M 




•^ 




•p^ 


^ 






^ 


m 


(U 


m 


fn 




u 




1 


CM 


• 

in 


CO 






<u 




^ 



.-I 3) 



— ■ rrv 



^ 



C3 
CM 



OO 



NO 



CM 



OO 



NO 



CM 



uj a. 5 

5 CO S 

yj =3 ijj 
> O Qi 

< zc o 



591 



HABITABILITY 
ByJ. S. Seeman, R. V. Singer, and M. V. McLean 
McDonnell Douglas Astronautics Company 

SUMMARY 



An overview is provided of the nmore outstanding findings regarding 
crew reaction to the environment afforded within the Space Station Simulator 
during the 90 -day confinement. Such areas as lighting, clothing, acoustic 
environment, and responses to the onboard habitability inventory are 
discussed. 

An exainination of crew responses indicates that the environnaent ade- 
quately supported the habitability needs of the four crewmen. In those 
instances where difficulties w^ere apparent, recommendations are offered 
for design alteration in future missions. 

INTRODUCTION 



On an overall basis, the results of the habitability inventory (an onboard 
questionnaire responded to by crewmen on test days 6, 21, 35, 49, 63, 77, 
and 90) are presented and discussed. Following this, specific significant 
features are discussed. These include the onboard illumination, acoustics, 
clothing, and thermal control. 

PROCEDURE 



Throughout the 90-day test at 2- week intervals, a questionnaire was 
administered to the crew consisting of over 50 items which were to be 
responded to with a rating of subjective acceptance (questionnaire provided 
in Appendix A). Responses w^ere converted to a numerical rating scale 
extending frona 4. 00 for the poorest items through 1. 00 for the best. All 
crewmen responded to each item in the questionnaire. These responses 
provide the primary source of habitability data. Questionnaire responses 
were divided into mean responses for various significant compartments or 
facilities in the chainber. For example, all questionnaire items relating to 
the equipment quarters are contrasted -with all questionnaire items relating 
to the w^aste management area. These are also related to the crew compart- 
ment and miscellaneous areas and facilities. The graph presented (fig. 1) 
displays the relationship among various areas and provides quantitative 
information on the overall habitability of the Space Station Simulator. In 
addition, an interesting finding results from plotting mean habitability as a 
function of time. Time course plotting shows the progress of adaptation of 
the crewmen to the environment. 

595 



RESULTS 

Of all the compartments within the chamber, the crew quarters was the 
miost acceptable. The acceptability of the crew quarters was followed by the 
acceptability of the equipnaent compartment after an initial 3-week adaptation 
period. While the crew quarters displayed a trend toward greater acceptability 
as time increased, miscellaneous features of the facility displayed a reverse 
trend. The hygiene area, after the first 3 weeks of adaptation, displayed no 
significant trend. 

Those areas initially judged to be least acceptable showed a rapid adap- 
tation to a nonainal level which tended to stabilize while those areas which 
displayed a higher initial acceptability show a gradual inaprovenaent over a 
longer duration. This can be seen in the difference between the curve for 
crew quarters compartment acceptability and that descriptive of the hygiene 
area. No area, while initially acceptable, showed decreasing acceptability 
as a function of mission duration. The overall miean for habitability over time 
shows an initial acceptability rising over time and then reversing at day 90. 
This curve is affected to a large extent by the downward trend in the naiscel- 
laneous areas and facilities which can be more properly characterized as 
miscellaneous facilities rather than areas. 

Crewmen's individual responses to various inventory itenas were averaged 
over the 90 days and an itena comparison was accomplished pernaitting the 
development of the habitability inventory itena ranks (table 1). Of 57 items 
indicated in the table, 55 fell within the fair through excellent range while only 
2 of 57 were ranked poor. Various reasons offered by crewmen for their 
rankings will be provided, especially in significant areas. Floors were rated 
as the worst itena gaining a score of 3, 96 out of a possible 4. 00, The reason 
for the floor receiving such a poor rating was not because of a structural 
inadequacy but because of the floor covering, which was a naaterial spray- 
painted onto the surface of the cold-rolled steel substrate. The Fluorel 
material sprayed over a General Electric silicone primer displayed very poor 
adhesion throughout the mission. As tinae progressed, crewmen were forced 
to renaove significant portions of the floor covering material to reduce the 
annoyance of the interference of floor covering naaterial with walking. Of 
approximately 1, 400 sq ft of naaterial applied to the substrate before the test, 
about 500 sq ft renaair^ed intact on the floor. The remaining naaterial was in 
very poor condition with naany holes and tears through to the substrate. 

Adhesion problems were probably the result of the long delay (approxi- 
mately 2 months) between application of the primer and application of the 
Fluorel overlay. During this 2 month period, the primer became overly 
dry and coated with dust. Although attempts were made to clean and prepare 
the primer surface before application of Fluorel, they were no doubt 
inadequate. Where adhesion was adequate, the material displayed satis- 
factory resistance to surface abrasion. 

Tears and holes in the flooring resulted from subsystena installation pro- 
cedures undertaken prior to test initiation and were rarely initiated by onboard 
personnel during the test. 

39^ 



The Pico projector was a device supplied by the University of Chicago 
permitting compact storage of chromiatic reading material, retrieval of this 
material, and display. The reason for its poor ranking resulted from a prob- 
lem in the equipment design such that focusing of the display could not be 
accomplished. The inability to properly display the miaterial resulted from, 
the inadvertent insertion of a shim in the lens system. Insufficient operating 
instructions existed for either project personnel or on -board crewm.en to 
rem.edy the situation. Had the inform.ation been available, the situation could 
have been corrected and the Pico projector no doubt would have received a 
higher ranking. 

The urine collector received a low ranking simply because it malfunc- 
tioned and was not repairable." The failure occurred during the first week of 
the mission, after which urine collection was accomplished through the use 
of graduated cylinders. This was an obviously unsatisfactory system for the 
collection of urine, but provided individual data on urine outputs that would 
have otherwise been unavailable. 

Throughout the section characterized as fair, naay be seen numerous 
references to the inadequacies of the audio support equipment available to the 
crew either for communication with outside personnel or for recreational pur- 
poses. This is a surmountable design problem which should be given increased 
attention in any future missions. The cause of these inadequacies was low 
audio fidelity and pickup and transmission of ambient noise. 

The appearance of body hygiene facilities in this section lends support to 
the idea that body hygiene provisions were less than adequate during the test. 
Particular difficulties mentioned by crewmen after and during the test were 
the feeling of oiliness as a residual to the use of Basic -H detergent which was 
the qole cleansing agent. This was reported despite the use of approximately 
2 gallons of wash water per day by each man. Another difficulty with body 
hygiene cited by the crewmen was the dripping of excess water onto the floor 
area im^mediately in front of the onboard sink as a consequence of washcloth 
bathing. 

The appearance of the electric! oven in this section yields the impression 
that it was relatively less desirable than the microwave oven for food prepar- 
ation. In fact, the electric oven was not used at all for food preparation. 
Data are available which indicate it was used no more than six times during 
the test and then only for the desiccation of some biological samples. 

PBI thermal -knit blankets presented difficulties in use by the crew. The 
primary reason for these difficulties was that they tended to slide off the 
bunks. Since they were required for thermal comfort this was an unacceptable 
feature. Crewmembers sewed or pinned the blankets to Durette bedding to 
prevent them from sliding off the bunks dxiring sleep. In addition, the crew- 
recommended the use of heavier blankets for future missions under these 
thermal conditions. 

Of all the storage volume allocations onboard the SSS, personal stor.age 
volumies were least acceptable. The reason for the lack of acceptability of 
personal storage volume provisions onboard the SSS is that they had been 
grossly underestimated and their location was inconvenient. 

595 



At the other end of the acceptance scale, storage requirements for food 
were satisfactory; the microwave oven was extremely well accepted as a 
means of reheating previously prepared freeze -dehydrated food; volumetric 
provisions in the equipment quarters were adequate; and light levels for the 
crew and equipment quarters were adequate. The latter finding reflects the 
ability of the crew to alter and adjust lighting conditions for 60 days of the 
mission and resulting perfect acceptance (ratings of 1.00). 

In contrast with previous studies, the habitability inventory indicates that 
privacy provisions were satisfactory and crew compartment noise character- 
istics were acceptable. Privacy was viewed by the crew as ability to be or 
feel alone without interference by other crewmem.bers. Except in the bunk 
area where additional bunk isolation curtains were recommended, privacy 
needs were felt by crewmen to have been satisfied. 

The Langley Research Center Complex Coordinator received a rating 
within the excellent category. This is gratifying when contrasted with findings 
with similar missions under sinailar circumstances on other devices in which 
crewmien discontinued performing psychomotor tasks as naission duration 
increased. The crew continued to perform on this device throughout the 90 
days with performance showing marked improvenaent throughout. Subjective 
comments of the crew indicated they enjoyed this device, not as a means of 
measuring their psychonaotor performance, but as a test of skill. They 
enjoyed competing with their own times to improve their performance. The 
ranking of 11 for this device versus the recreational provisions rank of 28 
indicates a mismatch in recreational provisions with the needs of the crew. 
This is corroborated by post -test crew comments as well as observations 
made throughout the mission. Because of a low level of interaction and because 
of personal proclivities, the crew chose not to enaploy the games which were 
available to them for recreational purposes even though they had been supplied 
at crew request. Rather, for recreation they engaged in individualistic 
activities such as reading, listening to music, creative writing, and watching 
television. 

Crew Clothing 

Onboard crew clothing consisted of three types: Burette garments fur- 
nished by MDAG^ polybenzlmidazole (PBl) garments, and Teflon gaiments. The 
latter clothing types were supplied by HASA !MSC, Crew Systems Division, for 
evaluation by our onboard cre-wmen. Material weights ranged from 3-75 oz/yd^ 
for the Burette through 8.75 oz/yd^ for Teflon. FBI materials were supplied 
in intermediate weights. 

All clothing received consistently good acceptability responses from, 
crewmen except the Teflon garments, which were described as too heavy, too 
warm, and somewhat "clammy" in our environment. Of the three clothing 
types crewmen preferred the weight of the Durette clothing supplied, feeling 
that it was consistent with the clo values required in our environm,ent. PBI 
and Teflon garments were preferred over Durette garments from the viewpoint 
of adequacy of tailoring. The primary difference between the tailoring of the 
two types of garmients was a fullness of the PBI garment and a clo se -tight - 
fitting configuration in the Durette garm.ents. 

396 



Durette clothing materials initially showed what appeared to be excess 
surface wear and exhibited "balling" of materials on the surface. These were 
the result of frequent contact with abrasive surfaces. This "balling" effect 
proved to be of no significance in the overall wear characteristics of this 
material. PBI garments displayed a "balling" effect also. This was consider- 
ably less than seen with Durette. PBI materials also wore quite well. 

Clothing was laundered onboard using a portable clothes washer and a 
snaall electric dryer. The detergent used for all laundering was Basic-H. At 
the conclusion of the mission, an inspection of the clothing revealed differ- 
ences in stain retention such that Teflon and Durette displayed m.ore retained 
discolorations than PBI. Apparently, Basic- H serves as an adequate stain 
remover for PBI, but not for Durette or Teflon. 

Acoustic Environment 

Criteria for the acoustic environment within the SSS were provided by 
NASA. They consisted of noise criteria adjusted (NCA) curve 60 for the equip- 
ment quarters and NCA 50 curve for the sleep quarters. Figure 2 presents 
the NCA plots for the octave bands from 45 through 11, 200 Hz. Comparing the 
criteria with obtained values measured onboard during the 90-day test indicates 
that the sleep quarters, with an overall sound pressure level of 69 db, more than 
satisfied the requirements imposed by NCA 50. The crew quarters rnore than 
satisfied the requirements imposed by NCA 60. The equipment quarters 
exceeded the NCA 60 requirements on 7 of 8 octave bands. Combining the crew 
quarters results with those of the equipment com.partm.ent would provide a 
curve more closely approximating NCA 60 requirements.. This was not done 
because the equipment quarters and the crew quarters were distinctly separate 
areas. The introduction of a bulkhead between those two areas to attenuate 
acoustic transmissions effected an approximate 6-db attenuation on the basis 
of overall sound pressure levels and as much as a 15-db attenuation in selected 
octave bands. 

Adherence to these imposed criteria resulted in acceptable ambient noise 
levels but Introduced the problem, of random, crew and equipment sounds, 
audible above background levels, as major irritants during sleep. 

Lighting 

A lighting experiment was conducted utilizing floure scent fixtures and 
rheostat controls. During the first 30 days of the test, the crew was required 
to live under lighting conditions closely approxinnating those expected onboard 
Skylab A. Reactions of the crew to these conditions were solicited during this 
period through use of the habitability inventory. During the middle 30 days of 
the test, the crew was encouraged to "experiment" with various light levels 
and to attempt to select the .most desirable levels for their tasks. During the 
last 30 days of the test, the crew was asked to adhere to the light level they 
had selected as most desirable during the middle 30 days. All procedural 
requirements were met including onboard weekly measurement of light values. 
Table 2 summarizes the findings of this evaluation. Fiiml settings shown 
reflect an approximate fourfold to fivefold increase in light levels compared 
with Skylab values. These reflect subjective preferences, not task ill^lmina- 
tion requirements. 

597 



Thermal Environment 

Characteristics of the onboard thermal environment have been presented 
elsewhere. In term.s o£ crew reaction, the crew quarters was somewhat pref- 
erable to the equipment quarters throughout the mission. Habitability inven- 
tory scores showed poorest acceptance of the thermal environment on days 6, 
35, and 49 with relatively better acceptability on days 21, 63, 77, and 90. 
Complaints on these items in the habitability inventory centered upon excess 
humidity, undesirably high air flows in the bunk area (which was altered by 
onboard crewm.en), condensation of m.oisture on cold surfaces (especially 
above the bunks), and high temperatures and humidity in the equipment 
quarters when high work outputs were required in that com.partment. 

CONCLUSIONS 

All available evidence suggests that the vast majority of habitability pro- 
visions were well within the range of acceptability for the crew. 

tractors have been identified which may be crucial to the acceptability of 
a habitat. These are: 

A. Crew naotivation 

B. Crew adaptability 

C. Duration of habitat utilization 

D. Initial acceptability of accommodations. 

Acoustics 

Crew response to noise levels indicated that the sleep area was the most 
acceptable from the standpoint of ambient noise. The crew quarters was next 
in acceptability. Least acceptable was the equipment quarters. 

More irritating than background noise were noises of other crewmen and 
equipment. These sounds were reportedly capable of awakening sleeping crew- 
men. This points to the inadequacy of acoustic isolation of the bunk area 
despite the overall attenuation of background noise. 

Clothing 

Tailoring of garments toward "fullness" is m.ore desirable than tailoring 
oriented toward close fit or "style". 

Lighter weight materials were more acceptable for our environment than 
the heavier weight materials. 

All tested materials display sufficient abrasion resistance to be acceptable 
for test durations of 90 days. 



598 



Laundering detergents must be matched not only to water recovery systems 
but also to clothing naate rials. 

Illumination 

The crew definitely preferred light levels of a higher intensity than Skylab. 
It should be noted, however, that no onboard tasks suffered as a result of 
using the Skylab levels. Accordingly, it may be concluded that the Skylab 
light levels are adequate for crew operations if auxiliary lights are available 
for those tasks with high acuity requirements. Given a situation wherein 
electrical power limitations are not as severe as Skylab, it would be desirable, 
to use the higher levels. 

Atnao sphere Thermal Control 

Greater attention must be focused upon effective temperature - a measure 
combining air flow, dry and wet bulb temperatures, and humidity - and work- 
loads for the provision of a more habitable thermal environment. Attention to 
each of these factors on an unintegrated basis results in less than desirable 
but adequate thermal accommodation. 

The apparent inadequacy in thermal accommodation can be accounted for 
to a large extent by insufficient provision for the thermal and humidity loads 
imposed by the solid amine CO2 concentration system. These loads were not 
predicted before the test start, and were therefore not included in the thermal 
control design requirements. Thermal and humidity load factors for this 
advanced subsystem were unavailable from the manufacturer at the time of 
its integration into the life support system. 



599 



Appendix A 
FORTNIGHTLY HABITABILITY EVALUATION 



The follo'wing questions are meant to direct your attention" to various factors 
involved in the overall habitability of the SSS. For example, there is a ques- 
tion concerning light levels in the general area of crew quarters, however, 
there are three possible sources of light in this area: (1) the fluorescent 
lamps, (2) the personal reading lights, and (3) the flashlight. The question 
does not identify specific features in the environment but is only meant to 
start you thinking about the area of lighting in general. For each question that 
evokes a non-neutral response, w^rite the question number and your comments 
on the answer sheets supplied. If you truly feel that your response to the 
question is neutral or deserves no comment, make no marks on the ans'wer 
sheet. Make sure to place your name and the test day at the top of the page. 

I. CREW QUARTERS 

1. Noise level 

serious moderate slight no 

disturbance disturbance disturbance disturbance 

Comment: 



Vibration level 



serious moderate slight no 

disturbance disturbance disturbance disturbance 

Comment: 



3. Light level 

excessive about right inadequate very inadequate 

Comment: 

4. Overall volume 

*too large about right too snaall much too small 

Comment: 



*Any space listed as "too large", "more than enough", etc. , means that this 
space could have been better used for some other purpose. 

400 



5. Storage volume-general 

about right 



more than 
enough 



Comment: 



Storage volunae— debris 

about right 



more than 
enough 



Conament: 



Storage volume— personal 

about right 



more than 
enough 



Comment: 



too little 



too little 



too little 



much too little 



much too little 



much too little 



8. Food Preparation Area 



excessive 
Comments: 



about right inadequate very inadequate 



9. Food Storage Area 



excessive 
Connments : 



about right inadequate very inadequate 



10. Recreation and Dining Table (consider aspects of size, comfort, 
height, area) 



excessive 
Comments: 



about right inadequate very inadequate 



11. Recreation and Dining Chairs (consider aspects of size, comfort, 
height, area) 



excessive 
Comments: 



about right inadequate very inadequate 



ij-Ol 



12. Bunks (consider aspects of size, comfort, height, ventilation) 
excellent good fair poor 

Comments: 



13. Bunk Area Privacy Curtain 



very useful 
Comments : 



useful 



annoying 



very annoying 



14. Privacy in General 

about right 



more than 
enough 



Comments: 



too little 



much too little 



15. Work/Rest Schedule 

excellent good fair 

Comments: (Identify split or common) 



poor 



16. Tenciperature, Hvimidity and Air Circulation 
excellent good fair 



poor 



Comiments: (Identify tennperature, humidity or air circulation if 
problem) 



II. EQUIPMENT AREA 

1. Noise level 

serious 
disturbance 



Comnrients : 



moderate 
disturbance 



slight 
disturbance 



no 
disturbance 



1K)2 



Vibration level 

serious 
disturbance 

Comments: 



moderate 
disturbance 



s light 
disturbance 



no 
disturbance 



3. Light level 



excessive 
Comments: 



about right 



inadequate 



very inadequate 



4. Overall volume 

too large about right 

Comments: 



too small 



much too small 



5. Storage volume— general 

about right 



more than 
enough 



Comments: 



too little 



much too little 



6. Work space 

more than 
enough 

Comments : 



about right 



too little 



much too little 



Temperature, Humidity and Air Circulation 



excellent 



good 



fair 



poor 



Comments: (Identify temperature, humidity or air circulation if 
problemi) 



8. Work Space Layout 
excellent good 

Comments: 



fair 



poor 



1^05 



III. GENERAL HYGIENE AREA 



1. Noise level 



serious moderate slight no 

disturbance disturbance disturbance disturbance 

Comments: 



2. Fecal Collection Facility- 
excellent good fair poor 
Comments: 

3. Urine Collection Facility 

excellent good fair poor 

Comments: 

4. Body Hygiene Facilities: Consider water temperature, size of towels 

and wash cloths, adequacy of cleaiising 
agents. 

excellent good fair poor 

Comments: 

5. Dryer 

excellent good fair poor 

Comments: 

6. Washer 

excellent good fair poor 

Comments: 



toil- 



IV. MISCELLANEOUS AREAS AND FACILITIES 

1. Internal Public Address 

excellent good fair poor 

C omments : 

2. Intercom to Outside 



excellent good fair poor 

Comments: 

3. Intercom to Internal 

excellent good fair poor 

Comnnents: 

4. Entertainment Speaker 

excellent good fair poor 

Comments: 

5. Entertainment Headsets 

excellent good fair poor 

Comments: 

6. Stepladder 

excellent good fair poor 

Comments: 

7. Bicycle Ergometer 

excellent good fair poor 

Conaments: 



405 



8. Recreational Provisions 



excellent 
Comments: 



good 



fair 



poor 



9. Skylab Clothing Ensemble Warmth (Fill in garment number. )** 
Jacket No. 



Trousers 


No. 


Shirt No. 




Drawers 


No. 


Socks No. 





Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 



Comments; 



10. Skylab Clothing Ensemble Conafort (Fill in garment number) ** 
Jacket No. 



Trousers 


No. 


Shirt No.. 




Drawers 


No. 


Socks No. 





Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 



Comments; 



11. Skylab Clothing Ensemble Wear (Fill in garment number) ** 



Jacket No. 



Trousers No._ 
Shirt No., 



Drawers No._ 
Socks No. 



Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


•Fair 


Poor 


Excellent 


Good 


Fair 


Poor 


Excellent 


Good 


Fair 


Poor 



ho6 



Comments: 

**Results of these items not readily quantifiable thus they have been 
omitted frona analyses presented in this paper. 



12. Dupont 4484 bed sheet * »» 

excellent good fair poor 

Comments: 

13. Durette bedding 

excellent good fair poor 

Comnments: 

14. FBI toweling *»* 

excellent good fair poor 

C omments : 

15. Terry cloth towels 



excellent good fair poor 

Comments: 

16. PBI thermal weave blankets 

excellent good fair poor 

Comments: 

^^' Durette Clothing Ensemble 

excellent good fair poor 

Comments: 

18. Durette Pajamas 

excellent good fair poor 

Conaments: 



♦♦♦Installation in SSS not accomLplished. Itemi omitted from analysis. 



19. Floor covering 

excellent good fair poor 

Comments: 

20. Personal lights 

excellent good fair poor 

Comments: 

21. Individual Pi coprojectors *** 

excellent good fair poor 

Comments: 

22. Group Picoprojectors 



excellent good fair poor 

Comments: 

23. Microwave oven 

excellent good fair poor 

Connments: 

24. Electric oven 



excellent good fair poor 

Comments : 

25. Refrigerator 

excellent good fair poor 

Comments: 



1^08 



26. Eating utensils 

excellent good fair poor 

Comments: 

27. Tool kit 



excellent good fair poor 

Comments: 

28. Freezer 



excellent good fair poor 

C omments : 

29. Body hygiene provisions (haircutting, shaving, etc.) 
excellent good fair poor 
Comments: (Identify as necessary): 

30. Langley Complex Coordinator 

excellent good fair poor 

Comments: 

31. RATER 



excellent good fair poor 

Comments: 

32. Human Describing Function Experimient 

excellent good fair poor 

Comments: 



i«)9 



33. Onboard laboratory work-space layout 

excellent jgood fair poor 

Comments: 

34. From an aesthetic viewpoint which compartment do you prefer?** 
C rew compartment Equipment compartment 

Sleep quarters Waste Management area 

Comments: 



35. If you could modify the interior color scheme of the SSS how would** 
you do so? 

i 

36. If you could change one color which one would it be and how would** 
you change it? 

37. Commients on areas and facilities not covered in questionnaire:** 

38. Aside from the technical problems encountered, would you recommend** 
this general configuration as a desirable living and working area for 
long-term space missions? Please explain. 



iflO 



en 
1^ 



O 
H 



CQ 



a 

^ 



> m 

PQ O 

^^ 

P 

I 

o 

05 






>— 1 

I 






RANK 
ORDER 


••1 ^^ C'l C8 •*• ^J CO CO 


»iiS9?9S?9i9S^§§Ss;»S3SIS 


in in 


MEAN 

ACCEPT 

SCORE 




S!giSSSSSS!^SSSSS8::iq» 


un 


S 

UJ 


HAIRCUT/SHAVE 
W/R SCHEDULE 
CREW COMPT EFF TEMP 
BUNK LIGHTS 
EQUIP COMPT EFF TEMP 
FECAL COLLECTOR 
LAB LAYOUT 
BEDDING 


INTERCOM/INT 
FOOD PREP AREA 
RATER 
CTT 

INTERNAL PA 
WASHER 
BUNKS 

ELECTRIC OVEN 
ENT HEADSET 
INTERCOM/OUT 
EQUIP COMPT NOISE 
BODY HYGIENE 
EQUIP COMPTWK SPACE 
EQUIP COMPTWKL/0 
PBI BLANKETS 
PERSONAL STOR VOL 
ENT SPEAKER 
URINE COLLECTOR 


PICO PROJECTOR 
FLOORS 


lda33V 


0009 ^ 


aivd § 


U00d| 


^£ 


«-cMi«i«rini0r^aBe 


n •- V- V- fo 


in t» 


3SSS 


•C K 
K O 






,fcuj 

1k° 


8 jif «s iq ^ ^ ^ ^ Pi ^ ^ 9 i9 


5B25555sl5§sg! 


gS2 
4n «4 


w o S 

S < M 






s 

UJ 


FOOD STORAGE 

MICROWAVE OVEN 

EQUIP COMPT GEN VOL 

CREW COMPT LIGHT 

EQUIP COMPT LIGHT 

CREW COMPT PRIVACY 

R&D CHAIRS 

CREW COMPT VOLUME 

EQUIP COMPT S VOL 

LRC-CC 

FREEZER 

GEN STORAGE VOL 

CREW COMPT VIBR 


DRYER 

ERGOMETER 

TOWELS 

DEBRIS VOLUME 

BUNK AREA PRIVACY 

EATING UTENSILS 

HYGIENE NOISE 

R&D TABLE 

CREW COMPT NOISE 

REFRIGERATOR 

TOOLS 

CLOTHING 

EQUIP COMPT VIBR 

LADDER 

REC PROVS 

PJs 


ld333V 


S lN31133Xa 


2 


0009 





l^-ll 



tu 


o 


09 

1 P 


^ 


H 


t- 


oc 


<» 


W 



S 8 S 



M 

Ul 

_l 
O 

tS p p 



Ul 



z z c 
2 H o 



in 



in a> in 



O 
5P S 5 5 



ZZ H 

s5t 



Ul 

-I 
Q 

|S 8 8 Ji 

ZZfc 

2t8 



-J 

Ul 

> 

UJ 



(0 

S 

3 



Z 
Ul 



s 

8 

t- 

z ^ 

Z Ul < 

O S Ul 

P Ul 5 

2 5 ^ t 

o 1 z z 

2 O < Ul 
OSS 

S Ul E 

S k ^ 

< ^ >< 

S S Ul 



oc 
o 



CO 



Ul 
(O 
CO 

< 

(O 
Ul 

> 

Ul 

-J 

00 



CO 



z 

Ul 

s 

oc 
< 



1 i 

8 I 



•- t t 

Z Z K 

Z lu Ul < 

o s s i 

^ H UJ 1 

S S S 8 

« * I fe 

» *" t 

u ^ 5 

oc < O 

U S UJ 



8 



UJ 

oc 
o 

> 
oa 

I- 
ui 

CO 

CO 

< 

CO 
Ul 

> 

Ul 



< 

z 

iZ 



Z 

Ul 



oc 

^ l- 

z 

UJ 



8 



S 8 



z z oc 

z m ^ < 

o s s & 

P H y 5 

3 I 1 z 

O S lu 

O ly S 

S ^ 5 

oc ^ a 

U S Ul 



kl2 



1.00 



T 

EXCELLENT 



1.50 



CO 

< GOOD 



ZD 
O 

o 



t i:2.50 



aoo 



FAIR 



< 

LU 

o 
o 

< 

> 






:r3.50 

POOR 

1 



4.00 




L£GEND 

• OVERALL HABITABILITY 

A CREW COMPARTMENT 

V EQUl PMENT COMPARTMENT- 

O HYGIENE AREA 

□ MISCELLANEOUS AREAS 
AND FACILITIES 



21 



35 49 
TEST DAY 



63 77 90 



Figure 1.- Habitability inventory. 



I4-15 




d 
't-t 
u 

U 

o 

I 

Si 

-M 
U 

Qi 

a 



o 
o 

<5 



CD 
S-i 

•■-I 



nvy3A0 



o* 



(yvaoyoiw zooo'o m siaaiOBO) 
13A31 3ynss3yd QNnos 



kik 



PSYCHOMOTOR EERPOIMfiHCE DORIKG THE 90-DffiC MftNBED TESfS 

By Rayford T. Saucer, Patrick A. Gainer, 

and Grady V. Maraman 

HASA Langley Research Center 

SUMMARI 

A psychamotor test device was placed aboard the 90-day-test chamber. Sub- 
jects Tjere tested fotir times daily. Data were analyzed for effects of confine- 
ment and for effects of selected trace gases. Long-term effects were not found; 
however, short-term relationships "between the gas levels and the psychomotor 
performance were found to he small "biit significant. 

mTRODDCTIOH 

A psychomotor test device developed at the NASA Langley Research Center 
was placed aboard the 90-day-test chaaiber. This device, commonly called the 
Laiigley Complex Coordinator (LCC), involves a serial, self -paced task including 
visual discrimination and psychomotor coordination of all four limbs, Ifetraman 
(ref . l) has given a conrplete description of both the test device and the per- 
foimance task. This description is not repeiated herein. 

The major ptirpose of the test progi^im was to examine the effects of long 
confinement on the perfoimance of a well practiced psychomotor task. In addi- 
tion, performance on this particular test device has been shown to be affected 
by a variety of physiological agents such as hypoxia {ret. 2) and alcohol 
(ref. l). On the basis of these results it was believed that performance on 
the LCC might be sensitive to physiological or behavioral changes induced by 
the presence of agents such as gaseous contaminants 4 

PROCEDURE AMD AKALTBIS 

Each siibject was trained on the LCC before the beginning of the 90-<3ay 
manned test. Scoares were approximately asymptotic before the test began. Later 
analysis has shown that there was a gradual increase in proficiency during the 
test. Each crewman was asked to perfoim a set of 100 trials four times per day. 
Scores were recorded as toteil time per 100 trials. Data were recorded for 
88 consecutive days for all crewmen . 

Data on average daily levels of CO, CO2, and total hydrocarbon partial 
pressures were recorded, and values of other system parameters such as tempera- 
ture and homiidity are available. 



415 




Conventional statistical analysis could not loe used 'becaxise of the small 
mmiber of subjects. In view of the fact that a time series of 88 data points 
for many variables was available, techniques adapted from stationary time series 
analysis were developed and appropriate statistics were derived. In particxilar; 
it was found that autocorrelation coefficients, ,qpuld he used to give an estimate 
of test-retest reliability. In addition these poeff icients. could be used to 
give an estimate of goodness of prediction over . extended periods of time. Sta- 
tistics for prediction based on both single test, scores and optimally weighted 
sets of scores were derived. 

In addition to the use of autocorrelation statistics, the use of cross- 
correlation techniques was explored. Cross-correlation techniques make it pos- 
sible to analyze the effects of system parameters on individual performance. 
Since the cross-correlation function is asymmetric, the cross-correlation coef- 
ficients can be used together with performance scores to deteimine whether or 
not performance scores will anticipate changing levels in system parameters. 
Either single scores or optimally weighted sets of scores can be used with this 
technique also. 

In addition it can be shown that either autocorrelation or cross-correlation 
coefficients can be used as estimates of population correlation coefficients if 
the individual coefficients are members of an ensemble. The standard error of 
estimate of the population coefficient can be estimated even though the number 
of subjects N is small. 

KESUIZDS 

Autocorrelation coefficients were calculated with time lags of 1 day for 
the first 10 days of the test. Ihus, in effect, the predictability of the score 
on the nth day can be calculated from the score on the first day. This set of 
coefficients was calcxilated from mean daily scores. Since there were nominally 
four scores per day, each daily mean score is subject to considerable smoothing. 
The results of this analysis are presented in table I. 

TABLE I.- ATOOCOEEELATIOH COEFFICIENTS CALCULATED FROM MEAN MILy SCOEES 





Autocorrelation coefficients for crewman - 


Lag, 
days 
















1 


2 


3 


k 





1.0 


1.0 


1.0 


1.0 


1 


.896 


.929 


.957 


.953 


2 


,8k-7 


.889 


.899 


.907 


3 


.796 


.859 


.88ij- 


.884 


h 


.735 


.828 


.870 


.861 


5 


.6jk 


.798 


.826 


.814 


6 


.653 


•778 


.812 


.791 


7 


.633 


.■jkQ 


.81? 


.Ikh 


8 


.592 


.717 


.768 


.698 


9 


.571 


.687 


.725 


.651 


10 


.551 


.667 


.739 


.651 



4i6 



It can "be seen that the autocorrelation coefficient calcxilated for a time 
lag of 1 day Is equivalent to calculating the test-retest reliahility for one 
suTjject over 88 day-pairs. The set of autocorrelation coefficients calculated 
for all suhjects for a 1-day lag is an ensemble, and each autocorrelation coef- 
ficient is an estimate of the population coefficient. In view of the relatively 
high values of the autocorrelation coefficients, no estimate of the population 
coefficient was deemed necessary. 

Since smoothing must affect the autocorrelation fimction and will of neces- 
sity obscure short time variance, the same analysis was carried out for a time 
lag of 1 test period. [Chese data are presented in tahle II. 

TABLE II.- AUTOCORRELATION COEBTICIENTS CALCULATED FROM TEST SCORES 





Autocorrelation coefficients for crewman - 


Lag, 
tests 






1 


2 


3 


k 





1.0 


1.0 


1.0 


1.0 


1 


.692 


.853 


.7iii- 


.815 


2 


.808 


.79^ 


.633 


.815 


5 


.611 


.795 


.612 


.778 


k 


.692 


.809 


.653 


.Tin 


5 


.635 


.750 


.592 


.7in 


6 


.6^k 


.750 


.551 


.7^1 


7 


.635 


.79^^ 


.510 


.7^1 


8 


.712 


.750 


Ms 


.70^4- 


9 


.539 


.706 


.612 


.70^^ 


10 


.673 


.721 


.633 


.70k 



It is obvious that the portion of the LCC score variance accoomted for 
hy test-retest correlation is somewhat less when the autocorrelation coefficient 
is computed for a time lag of 1 test period. These results indicate short time 
variance -vdilch may he presumed to he due to hoth random effects and some sys- 
tematic effects from other variables. 

Cross-correlation coefficients were calcxilated for the relationship 
between LCC scores and both CO and CO2. Th.e correlations between the mean I£!C 
scores and mean partial pressures for CO and CO2 are presented in table IH. 

TABLE in.- CROSS CORRELATION HETWEER LCC SCORES AND GAS PARTIAL BRESSURES 



Gas 


Cros0-correlation coefficients for c3rewma,Ti 


- 


1 


2 


3 


k 


CO2 
CO 


-0.138 


-O.PIO 
.19T 


-0.126 
.251 


-0.200 

.iin4 



417 



Kiere is evidence of a small "but significant correlation for 'botli gases. 
The coefficients as presented are significant at a level of approximately 0.05. 
However, it was fOTmd that there is some covariance in the data. The CO and CO2 
pressures were found to have a correlation of 0»300, which is significant heyond 
the 0.01 level. 

If ensemble averaging is applied, it is fotjnd that the estimated population 
correlation coefficient for the relationship hetween the IJCC scores and the CO2 
partial pressure is approximately -0.250. when partial correlation adjustment is 
made for the CO-CO2 covariance. The estimated population correlation coeffi- 
cient for the relationship "between the I£!C scores and the CO partial pressure 
is 0.252 when this adjustment is made. Since both these coefficients have over 
300 degrees of freedom, "both are significant at levels approaching 0.001. 

DISCUBSIOfr 

The data presented in tahle I are essentially estimates of the predictabil- 
ity of mean or smoother scores sad hence are estimates of the long-time stabil- 
ity of the psychomotor skill. It is believed that there is evidence to support 
the conclusion that over a long time period the KJG score is highly predictable 
and hence quite stable. In fact, there is evidence that learning continued to 
take place for the duration of the test. This learning was of such a degree 
that removal of most of the effects of learning by fitting a straight line as a 
first-order approximation of the learning curve was necessaiy to avoid the pos- 
sibility of spurioxis correlations. 

The data presented in table IH are based on adjusted LCD scores and the 
gas partial pressures. These correlations, while small, are believed to be 
valid. Both the absolute partial pressures and the variations in pressure were 
relatively small and thought to be below the level of significant" physiological 
reactivity. It is thought that the results of this preliminary analysis are 
suggestive of the need for further research directed towards the use of behav- 
ioral methods as indices of trace gases. 

These Inferences are further supported by the fact that for both gases the 
relationship. suggested by the correlation coefficients is consistent with known 
physiological data. At low levels CO2 is known to be a stimulant, while it may 

be suspected that at some levels CO will have a negative effect on performance., 

CONCLUDING TREMAHKB 

A psychomotor test device was placed aboard the 90-day-test cham"ber. Sub- 
jects were tested four times daily. Iteita were analyzed for effects of confine- 
ment and for effects of selected trace gases. I^ng-term effects were, not found j 
however, short-term relationships between the gas levels and the psydtiomotor 
performance were found to be small but significant. The analysis presented 

in8 



herein Is only a small portion of that planned for the data gathered during the 
90-day manned test. 



BEFERE^BS 



1. Maraman, Grady V,: Effects of Alcohol on Complex Behavior. Ih.D. Ihesis, 

Virginia Commonwealth TJhiv. , June 1970 • 

2. O'Connor, William P.j and Pendei^grass, Geoifge E.: Task Interruption and 

Performance Decrement Following Eapid Decompression. Aerosp. Med., 
vol. 57, no. 6, June I966, pp. 615-617. 



4l9 



CREtf FEKFQRMAJNCE OS SIMULATED CdTEROL TASKS 

By R. Wade Allen and Henry R. Jex 

Systems Technology, Inc. 
Hawthorne, California 

SUMMAH7 

In order to test various components of a regenerative life sujrport system 
and to obtain data on the physiological and psychological effects of long- 
dirration exposure to confinement in a space station atmosphere, four carefully 
screened young men were sealed in the McDonnell Douglas Astronautics Space 
Station Simulator for 90 days with no pass-in' s allowed. Under contract to 
the NASA Ames Research Center,* Systems Technology, Inc., administered a 
tracking test battery during the above experiment. The battery included a 
"clinical" test (Critical Instability Task) related to the subject's dynamic 
time delay and a conventional steacSy tracking task during which dynamic 
response (describing functions) and performance measures were obtained. The 
subjects were extensively trained prior to confinement and generally reached 
asymptotic performance levels. 

Good correlation was noted between the clinical critical instability scores 
and more detailed tracking parameters such as dynamic time delay and gain- 
crossover frequency. The levels of each parameter spans the range observed 
with professional pilots and astronaut candidates tested previously. The 
chamber environment caused no significant decrement on the average crewman's 
dynamic response behavior, and the subjects continued to improve slightly In 
their tracking skills during the 90-day confinement period. Seme individual 
performance variations appeared to coincide with morale assessments made by 
other investigators. The ccxnprehensive data base on human operator tracking 
behavior obtained in this study should be further correlated with concurrent 
psychological, physiological, and environmental data obtained by others during 
the 90-cl-ay confinement study. 



*This research was sponsored by the Man-Machine Integration Branch of the 
MSA Ames Research Center under Contract HAS 2-4405 (Modification-5). The tasks 
and associated hardware used in this stixdy were previously developed under the 
same contract. M. Sadoff and N. McFadden have been the Ames Project Technical 
Monitors throughout the program. 

421 



INTRCOUCTiQI!! 



A 90-day sealed chamber test of a regenerative life support system was 
performed at the McDonnell Douglas Astronautics Corporation (MDAC) under NASA 
Contract MS 1-8997 from the Langley Research Center. Among the stated objec- 
tives of the official test plan and procedures (Ref. l) are the following: 

".-. .5. To demonstrate man's capability. . .for in-flight moni- 
toring of necessary hijman.. .parameters. 

6. To obtain. . .data that will assist in determining the 
precise role of man in performing in-flight experiments... 
and... in validating mathematical models of [manned] space 
missions. 

7. To obtain data on physiological and psychological 
effects of long-duration exposure to confinement in the cabin 
atmosphere . . . ." 

To accomplish these objectives, four men, carefully screened for ccmpatibility 
with each other and with a confined environment, were sealed in the MDAC Space 
Station Simulator (SSS) for three months with no pass-in 's allowedj also, only a 
limited number of pass-outs allowed for medical sampling purposes, teie primary 
workload of the subjects included monitoring and maintenance of SSS life support 
equipnent and monitoring and recording their metabolic, medical, and mood char- 
acteristics. The SSS environment was "closed-cycle" and included a subnormal 
air pressure of 5/^ atmospheres with normal oxygen partial pressure. 

This program also provided a unique opportunity to evaluate certain other 
psychcmotor and cybernetic functions in a realistic space station environment 
(except for zero-gravity) and under operational type work-rest cycles and 
ambient stresses. Among the more important of such psychomotor tasks are the 
broad class of tracking tasks: star tracking for navigation or astrononical 
p-urposes; telescope pointing for earth resource or reconnaisance purposes^ fine 
jbuning of apparatus for research or ccaBmunications purposes; and, last but not 
least, piloting tasks such as rendezvous in orbit and reentry into the earth's 
atmosphere. (At least one of the crew members is likely to be a pilot or 
trained as a pilot for such emergencies . ) 

In order to measure behavior appropriate to such tracking tasks. Systems 
Technology, Inc., under sponsorship by the MSA Ames Research Center's Man- 
Machine Integration Branch, provided a battery of tracking tasks to be per- 
formed during the 90-day mission. The objectives of this experiment were: 

1. To obtain a simple "clinical" measure of the crewmember's 
visual -motor dynamic performance on a routine basis using 
the so-called "Critical Instability Task " (Ref. 2). 

2. To obtain ccsnprehetisive measures of the intrinsic dynamic 
response properties on a less frequent basis by means of 
advanced cross-correlation techniques and to correlate 

422 



this standard tracking-task data with the critical insta- 
bility measure. 

5. To present data obtained in this tracking experiment for 
correlation vrith medical physiological and psychological 
data from other experiments run concurrently. 

The tracking task test battery and associated apparatus employed in this 
experiment were developed under MSA sponsorship and are detailed in Refs. 2-6. 
Systems Technology's role in the present experiment was to provide test speci- 
fications and experimental design and procedures; to participate in indoctrina- 
tion and training; and to reduce and analyze the data. Douglas personnel were 
responsible for integrating the equipment and tests into the 90-day Experiment 
and for administering the control task test sessions. 

COin^RQL TASW AND MESBIMNTAIi SETUP 

Control Tasks 



The psychcmotor tests used in this experiment are continuous, canpensatory 
visual-motor tracking tasks. A general block diagram representation of these 
tasks and associated data measures and analysis is shown in Fig. 1 . A thorough 
description of these tasks is given in Refs. 5 and 6. Basically, the subject 
is required to control the motion of a 1-uminous horizontal CRT line with an 
iscxnetric (force) control stick whose oatpat controls a dynamically unstable 
controlled element [first-order: Yc-r = ^i/(s ^ ^i)j second-order: Xcp = 

X2/s(s--X2)]' If "^^s subject provides the appropriate dynamic equalization 
behavior he will be able to not only stabilize the man-machine system, but to 
minimize CRT line motions away from the null point or reference line. Two 
variations of this unstable tracking task employed in the present experiment 
are described below: 

1 . Critical Instability Task 

The subject is required to maintain stable control as the controlled 
element's instability is steadily increased. No external disturbance need 
be introduced in this task because "remnant" noise sources internal to the 
human operator (e.g., unsteadiness, tremor) provide ample excitation for 
the unstable element. In the face of the increasing instability the sub- 
ject will lose control of the task at some point because the line diverges 
off the CRT more quickly than he can exert compensatory control action. 
The degree of instability, Iq, at which the subject loses control is termed 
his "critical instability" score. It is roughly equal to the inverse of 
the operator's dynamic time delay as shown in Refs. 2 and Ji. 

The control of simple first-order divergent dynamics is called the 
first-order critical task and requires the operator to act as a simple 
gain (i.e., the operator's stick output looks like a scaled version of 

k23 



the system error signal including a time shift equal to the operator's 
dynamic time delay). Controlling a first-order divergence in series with 
a pure integrator is called the second-order critical task . In controlling 
these dynamics the operator must effectively cancel out the efTect of the 
integrator by providing what we term first- order lead equalization in order 
to stabilize the control dynamics. (Lead equalization is equivalent to 
rate perception or error signal prediction. ) Generation of this lead 
equalization requires additional mental processing time (Ref . 7) which 
increases the operator's effective dynamic time delay. Thus for the second- 
order critical task the operator can't achieve as high a critical insta- 
bility score as with the first-order task. 

The operator's basic effective time delay, as measured by the first- 
order critical task, is composed primarily of neural conduction time delays 
and neuranuscular dynamics of the arm. Thus performance on the first-order 
critical task is a measure of basic neuromuscular dynamics, while the 
second-order task measure includes a component due to higher center 
involvement . 

The critical task is easily administered since it only requires about 
one minute per trial and a single number is recorded at the end of each 
trial. Therefore, the first- and second-order critical instability tasks 
were selected to be administered routinely d-uring the 90-^a'y confinement 
test . 

2. Steady "Subcrltical" Tracking Tasks 

For steady tracking tasks the instability level of the unstable dynamics 
is held constant at a value well below the typical subject's critical insta- 
bility score. An unpredictable command input is introduced into the 
tracking loop as shown in Fig. 1, and the subject is asked to maintain 
minimum tracking error during runs lasting approximately 2 min. Using 
special apparatus to be described later, the error signal is Fourier ana- 
lyzed and performance data are computed during the run. These data are 
further reduced off-line, via a time-sharing computer program, to obtain 
the subject's open-loop describing function and task performance. The 
describing functions are fitted with a three-parameter dynamic response 
model, and the resulting loop closure properties are interpolated. Key 
parameters presented herein include: 

Crossover frequency (cdq), the unity- amplitude frequency of the open 
loop describing function, a measure of the subject's gain. 

Phase margin (J^), a measure of system stability margin related to 
the closed-loop damping ratio. 

Dynamic time delay (tq), the subject's visual -motor time delay in 
a continuous tracking task including neural and mental delays 
and neuromuscular lags. 



k2k 



The performance measures include: 

formalized error variance {a^/a?^)^ the ratio of tracking error 
variance to the variance of the task input. 

Error coherence (pg), the percentage of total variance predicated 
hy (correlated with) the describing function measurements. 
The remaining error power (1— p§) is due to the subject's 
internal noise (remnant). 

For this escperiment we chose to include both first- and second-order 
subcritical tracking tasks that are djmamically equivalent to the first- 
and second-order critical instability tasks. The first-order instability 
was set at IvL = 2 rad/sec, and the second-order case was set at A2 = 1.25 
rad/sec. Although these tasks allow a detailed assessment of the subject's 
dynamic response and noise properties, they require longer trial durations 
and a large amount of on-line data collection and reduction. For this 
reason they were run less frequently than critical tasks during the 90-day 
test, and were employed to provide realistic tracking task data to corre- 
late with the critical instability scores. 

Test Setup and Equlpnent 

The experimental layout and apparatus axe shown in Fig. 2. The test admin- 
istrators conducted the experiment fron the control roan where the task comput- 
ers were located. The Controlled Element Computer (CEC) provided the unstable 
dynamics for the tracking tasks, and autonatically increased the instability 
during critical task runs as shown in Fig. 1. The Describing Function Analyzer 
(DFA) provided the subcritical tracking task input, Fourier analyzed the tracking 
error signal, and measured various performance parameters. 

The display and control stick, connected to the computers through a 100 -ft 
cable, were located in the space chamber recreation area. The Douglas Test 
Administrator communicated with the crewmen through an intercom, and also via 
Interconnected "ready" lights located on the subject's display and the controlled 
element computer. 



TBAIMMi 

Crewmen begari training on the first- and second-order critical tasks four 
months prior to canmencing the 90-day confinement period. This training con- 
sisted of approximately 5 one-hour sessions spanning a five-week period. At 
each session the crewmen would track 2 three-trial blocks of the first-order 
critical task and 2 five-trial blocks of the second- order critical task. These 
Xci and Xcp training scores are plotted in Fig. 3(a) • It is evident that 
aU crewmen reached stable levels of critical instability within about 100 
trials of distributed practice. 



i)-25 



Training of the steady tracking tasks was commenced immediately after 
critical task training. Because of the dynamic similarity between the critical 
and subcritical tasks, a favorable transfer of training is assured. The crew- 
men tracked three first-order and three second-order runs per session for 
approximately ten sessions spanning a four-week period. Dynamic response data 
for the first- ajid second-order tasks is plotted in Figs. 5(b) and 5(c). From 
Figs. 5(^) and 5(c) the crossover gain, (u^, shows a gradual increase with 
trainingj while the stability margin, <jijj^, shows a concurrent decrease. Stable 
training levels were achieved in all cases except for Crewman k on the second- 
order task. He had significantly less exposure to this task than the other 
crew members, and he later exhibited correspondingly larger learning effects 
during the confinement per'tod. 

90-DAY COHFIKEMEINT TESTS 

Gfeneral 

During the confinement period, three trials of first-order and five trials 
of second-order critical instability task were administered routinely every 
Monday, Wednesday, and Friday, following the midday meal. These data formed 
the core of our experimental design, and represent a base tram, which other 
tracking data can be ccmpared and extrapolated. Steady tracking sessions were 
performed twice a week, one session for each order. These sessions began with 
the critical instability trials of the equivalent dynamics in order to provide 
a warmup and also to provide concurrent correlations between Xq and the more 
comprehensive measxires of steady tracking behavior. 

The crewaem were split into two shifts, with Crewaen 1 and 2 on a ncminal 
day shift (OTOO-2500 W) arui Crewmen 5 and ij- on a graveyard shift (21CX)-1500 Hr). 
Illtmiinatlon was. held constant inside the simulation chamber, and all indications 
are that Cre-wmembers 5 and k oLuickly adjusted to their abnormal work shift. Test 
sessions were conducted after the mldshift meal (nominally 1500 Hr for Crewmen 1 
and 2, and 0200 Hr for Cre'waen 5 and k). All test sessions began with a warmup 
critical instability trial. 

Critical Instability Eestilts 

Weekly mean critical task scores (averaged across the solely Xc sessions 
for each week) are plotted in Fig. k. Generally, thtese scores were very reli- 
able (low residual variance) and showed a consistent stratification among crew- 
men. Crewman 1 evinced the moat variable performance, with a definite dip 
in scores during the initial confinement period ccmpared with his preconfineiment 
baseline. This dip was followed by a return to performance levels significantly 
above his preconflnement baseline. There is one very consistaat dip in perfor- 
mance for all crewmembers diirihg Week 9, In a dis cxks ion with M. V, McLean of 
McDonnell Doxiiglas it was determined that a definite dip in morale occurred in 
this period. 



426 



There is a consistent, eilbeit small, improvement trend apparent over the 
90-day period in all cases except for Crevnnan 5 on the second-order task. 
Experience suggests that this reflects a residual improvement in the neuro- 
muscular system due to continuous practice beyond the initial training asymp- 
tote — much as in any athletic skill involving strength. 

Analysis of variance procedures applied to the data showed subjects and 
•weeks to be significant main effects. The subjects by -weeks interaction was 
also statistically significant. 



Steady Tracking Results 

The steady tracking behavior and performance data are plotted in Fig. 5. 
(The critical instability data shown here were obtained at the beginning of 
each subcritical tracking session, and were not included in Fig. h.) The 
steady tracking data are often missing because these sessions had a somewhat 
lower priority than the critical task sessions and were not performed for a 
variety of reasons. 



The dynamic response data (odc and ^) and critical task scores (X^) seem 
to remain fairly consistent and similar in level over the 90-day period. The 
normalized error and error coherence performance measiires (o^/af and p|) show 
considerable variations, however. Cre^wman li-'s tracking errors are signifi- 
cantly higher than that of the other crew members. This result seems to be due 
primarily to an intrinsically hi^er remnant level as evidenced by his lower 
error coherence scores for both the first- and second'-order tasks. 

Crewmen 1 and k were still learning the second-order steady tracking task 
during the first half of the confinement period, as reflected in their nor- 
malized error scores. This result seems to be primarily due to c3ynamic 
response effects as both subjects show a corresponding increasing trend in 
crossover gain during the first half of the mission. 

The ccanprehensive variety of measurements m.£ide during steady subcritical 
tracking will help in interpreting vao-iations in tracking behavior and per- 
formance. A good understanding of the theoretical relationships among the 
above parameters exists (e.g., Ref. 6), and this will be used to unravel the 
seemingly conplex and anomalous variations exhibited in Fig. 5. 

Correlation Be-|;ween Subcritical and Critical Task Results 

One of the objectives of this, experiment was to tie in the dynamic response 
measurements obtained during steady tracking tasks with the critical insta- . 
bility scores. Some correlation of critical and subcritical task data is shown 
in Fig. 6. Effective dsmamic time delays (Te) were derived from the dynamic 
response measurements obtained during subcritical tracking runs, and the inverse 
of Te should be directly related to critical task scores as discussed in Refs. 2 
and 3« The good correlation of Tq"'' versus Iq scores obtained during each 

427 



subcritical tracking session (r = 0.74)' is shown at the top of Fig. 5 for both 
first- and second- order tasks. Because it is viltimately hounded by Te~^ and 
hence by Xq, crossover frequency (guc) lias also been shown to correlate with Xq 
(Refs. 5 and 6). The good correlation in this, experiment (R = O.&i-) is shown 
at the bottom of Fig. 5. The present correlations, with initially naive sub- 
jects, are somewhat less than similar ones made in Refs. 5 and 6 among profes- 
sional pilots, but the trends and fitted lines are similar. The good tie-in 
of the present tracking behavior, performance, and critical instabilities 
with previous data constitute a strong validation for the generality of the 
models and interrelationships observed. Further analysis is now in order 
to compute the empirical factors via the theoretical models and the present 
data. 

The absence of profound decrements in the performance data, tracking 
behavior, or critical instability scores should cane as no surprise since the 
chamber environment was maintained in a generally satisfactory state . 

OamLWim BEMABKS 

Crewmen performance in this experiment agrees quite favorably with that of 
experienced pilots and test STibjects tested previously. ITo seilous degradations 
in performance were noted dxirinig the mission, and in fact there appeared to be a 
slight improvement trend throughout the 90-day period. Some dips in individiml 
performance seem to correlate with subjective attitude and morale data not 
shown, so correlations of tracking data with other psychological measurements 
as well as with physiological and environmental data should be ptirsued. 

A rich harvBSt of statistical data on manual control behavior has been 
obtained in this experiment. Its further analysis should tell us a great deal 
about the consistency and measurability of h-uman dynamic response properties 
over an extended period of time under confined conditions. 

The control task equipnent functioned properly throu^out the mission, even 
though the CRT display and control stick were subjected to the simulator sub- 
atmospheric press-ure. In spite of the apparent conrplexity of the equipnent and 
test protocols, both the crewmen ajad test administrators quickly became profi- 
cient in the experiment procedures. Test sessions for one subject typically 
required less than 15 min. Thus the simpler equipnent and tests being planned 
for future orbital use by astronauts should meet with good acceptance and allow 
us to obtain in-depth information regarding the space environment's effect on 
human dynamic response properties , 



lj-28 



1. Houghton, K. H., Test Plan and Procedure; Operational Ninety-Day Manned 

Test of a Regenerative Life Support System KASA-LRC Contract HAS 1-8997 , 
McDonnell Douglas Astronautics Ccmpany Kept. DAC-65303, June 1969. 

2. Jex, H. R., J. D. McDonnell, and A. V. Phatak, A "Critical" Tracking Task 

for Man-Machine Research Related to the Operator's Effective Delay Time ; 
Part I. Theory and Experiments with a First-Order Divergent Controlled 
Element, MSA CR-616, Nov. 1966. 

3. McDonnell, J. D., and H. R. Jex, A "Critical" Tracking Task for Man-Machine 

Research Related to the Operator's Effective Delay Time; Part II. 
Experimental Effects of System Input Spectra, Control Stick Stiffness , 
and Controlled Element Order , NASA CR-Gjk, Jan. 1967. 

h. Jex, H. R., J. D. McDonr:^!!, and A. V. Phatak, "A 'Critical' Tracking Task 
for Manual Control Research," IEEE Trans ., Vol. HPE-7, No. k, Dec. 1966, 
pp. 138-lii-5. 

5. Jex, H. R., and R. W. Allen, "Research on a New Human Dynamic Response Test 

Battery; Part I. Test Development and Validation; Part II. Psychor 
physiological Correlates," Proceedings of the 6th Annual Conference on 
Manual Control , Air Force Institute of Technology, Wright-Patterson 
AFB, Ohio, 7-9 Apr. 197O, pp. 7^3-777. 

6. Jex, Henry R., and R. Wade ALLen, A Psychomotor Task Battery for Manual 

Control Performance : Development, Validation, and Some Psychophysio- 
logical Correlates , Systems Technology, Inc., Tech. Rept. ^J^-^ , 
Jan. 1970..; 

7. McRuer, D. T., L. G. Hoflnann, H. R. Jex, et al. New Approaches to Hianan- 

Pilot /Vehicle Dyxiamic Analysis, AFFDL-TR-67-15O, Feb. 1968. 



11-29 



CO 



m 
< 

co 

z 



< 
o 



o 



b 


1. 


>^ 




•* 




o 




U 




z 




!-< 




< 


<-> w 




Q 




guj to 






c 


<o q: 




o 
Q 


o 


tijOUJ 

fv q: K 




<u 


3 


SHAI 
CH P 
)MPU 




c 


"S 




•»- 


rr 




O 




j^^y 


>,! 


HOQ 


4- 




o — 


a> 


.t o 


W U 


8-^ 

w 



CO 
CO 

< 



o 

z 

o 
< 
q: 



< 

^< 

oc 
o 
m 

z> 

CO 

>- 
a: 
< 



CO 



3 a> 
o o 
U.O 






•a 


♦- 


►-« 




■e- 


9> 


3 


*- 

3 


V" 


o 




N 








je 


o 

c 
< 


10 

o 
o 

•- ®« 




UJ 


o 

c 


3 

o 


I. 

3 


II 


II 
III 


l-O) 
II 


o 

3 


II 


O 






Ctl 


c 




U. 


a: 


E 


UJ 




■♦- 



z 
o 

CD UJ 

a:< 

Oz 

C05 

UJ^ 

o 



ca 

•1-4 
(» 



OQ 



03 

s 

03 

•1-1 

a 
u 



2 

•f-H 

1^ 



1^50 



CRT DISPLAY 
AND ISOMETRIC 
CONTROL STICK 



Life Support Equipment 
Bicycle Ergonometer 
Complex Coordinotion Tester 





SPACE STATION SIMULATCm 



Display/Computer 

aoMUmm 



SUiJECT PERFORMING TRACKfN© 
TASK INSIDE TEST CHAMBER 



Comminicatlor) t 
I 



Closed 
Circuit 

TV 
Monltws 




TEST ADMINISTRATOR CONWJCTIN© 
CC^TROL TASK 
EXPERIMENT TEST SESSION 





TEST CONTROL AREA 



CONTROLLED ELEMENT COMPUTER 

mo 

DESCRIBING FUNCTION ANALYZER 



Figure 2.- Control task apparatus and experimental setup 
for the 90 -day confinement study. 



431 



Crewman: ' 



-2.- 



-3, 4 



Critical 

Instability 

Scors , 

(rod /sec) 



Critical 

Instability 

Score, 

(rad/sec) 



I St Order Tasl( , 3 Trial Means 




6 

2nd 



^ 



le 24 30 36 42 48 54 60 66 72 78 
Trials from Start 

Order Tosk , 5 Trial Means 
■■v-\-~.y~'- 



84 90 96 102 108 114 



February 



March 



May 



10 



20 30 40 50 60 70 80 90 100 110 120 130 140 
Trials from Stort 



(a) Critical task data. 



10 20 

Preconfinement 

Baseline 



May 



_L- 



_1_ 



6 12 
Preconfinement 
Baseline 



8 

Crossover ^ 
Frequency, 

(rod/sec) 2 






_JL I 1 1_ 



50 

40 
Phase 
Margin, 30 

9m 20 
(deg) 

10 





- 










V 










:^ 


^^i^ 


%Sp^^ 


J^ 


^'''C.:.>-^'>cC>^_„r. 




March 

1 1 1 1 


April 

II 1 1 


1 


May 

1 II 1 



9 12 15 18 21 24 27 30 
Trials from Start (post critical tasl< training) 



33 36 39 



("b) First-order steady tracking. 



^._,-.«/:- 



^ir--^^ 



_1_ 



May 



_!_ 



3 6 

Preconfinement 

Baseline 



Crossover 


6 


Frequency, 


4 


"c 




(rad/sec) 


2 









50 




40 


Phase 




Margin, 


30 


*m 


?0 


(deg) 






10 

















- 














1— >= 


-,.., ^^, 


.^^Si^;.--^"*-":: 


-^'- 


=<;3=> 


<^ 






1 1 


1 1 1 


1 


1 1 




1 1 1 1 1 



'^^'^^.r.'?^'^. / 



9 12 15 18 21 24 27 30 33 36 39 

Trials from Start (post critical task training) 

(c). Second-order steady tracking. 

Figure 3.- Training data. 




3 6 

Preconfinement 
Baseline 



^32 



8 - 



Critical 

Instability 

Score 

^c 6 

(rod/sec) 



Crewman 

' ^•"•••^ T I St Order 

2 O O I Residual Variance 

' jo- = .4rad/sec 




~Q D^ 



/0 {D Q O^ 



A 




J 2nd Order 
. jResidual Variance 
> Day{nominal) jj a =.28 rod /sec 

6 13 20 27 34 41 48 55 62 69 76 83 93 

LJL_1 \ 1 I 1 I I I 1 1 L 

'^ ' 2 3 4 5 6 7 8 9 

Weeks From Chamber Entry 

Figure 4.- Weekly mean critical instability scores during 
the 90 -day confinement period. 



Preconfinement I 
Base Line 






10 II 12 " Post 

Confinement 



hZ>-^ 



FIRST-ORDER TASK 



S" s-2 



Crew/nan : 



10 

8 

Critical 

Instability ^ 

Score, 

X •* 

*e 
(rod/sec) 



Base Base 

Line Line Weeks from Chamber Entry 

I 2.1 2345678 9 10 II 12 

— I t-Vt 1 1 1 1 1 1 r — I 1 1 1 — 



-J I I I I i_ 



1 I I 



SECOND-ORDER TASK 

■2. 3. 4 .. . 1.25 

V s(s-l.25) 

Base Base 

Line Line Weeks from Chamber Entry 

I 2.1 234 5678 910 || 12 

T t-Vt 1 1 1 1 < 1 1 1 1 1 r 




10 
8 

Crossover 6 
Frequency, 

«c 4 

(rod/sec) 



-1 1 1 1 1 1 1 1 1 1 T" 



-1 r 



Phase 30 
Margin, ^^ 



Normalized 



IX} 



Error, 
af .6 




T 1 1 1 1 1 1 1 1 1 1 I 1 r 



><><.......:>-<: 



I I I I I I I I 1 I I I I 1- 



1 1 1 1 1 1 — 1 r— 


1 T- 


-I -1 1 1 


: \ 




- 


- \ ^ ,-- 




- 


: V-^-^,--' 




--— - 


- -/!> ^''^^^~~- 




- 


■•' ^ ~-— -' N. \ 






- •-;/ M- 


""^^ 


f~.. 


1 1 1 ( 1 1 1 V~ 


--r- . 


I 1 1 1 




I 'I 1 J 1 I 1 I -1 L 



^- 



Error .6 
Coherence, 
-2 4 



Pi 



-\ 1 1 1 1 1 1 1 1 1 r — I r r 



N.* 



-UUl 1 L. 



_i 1 r I 



-I 4- 



T 1 1 T 



-I 1 1 1 1 1 T 



I 2-1 234 56 7 8 9 10 II 12 
Base Base Weeks from Chamber Entry 

Line Line 




I 2 ^\ 2345678910 II 12 
Base Base Weeks from Chamber Entry 

Line Line 



Figure 5.- Comparison of tracking-session data 
for the 90 -day test. 



k--^ 



12 



10 

Inverse 
Dynamic 
Time 8 
Delay, 

(sec"') ^ 



▼ ▼ 



I St- Order Task 



m^Ai}iA^ 



m % ■ 




■ 4 #4 ^^ 






2nd-0rder Task 



Tg =-.04 + l,52Xc 
R =.74 



°oMr 



Crewman : 

▲ = I 

• = 2 

▼ = 3 

■ = 4 

_J 



8 



Crossover 
Frequency, 

<uc 61- 

{ rod /sec) 




3 4 5 6 7 

Critical instability, Xq (rad/sec) 

Figure 6.- Correlation between critical instability score 
and steady tracking data. 



8 



" ^55 



EFFECTS Of mm DURAIION COKFTKEMENT OH SHOHD-IERM MMOET 

:^y R. Jfexk. Patton and Clayton R. Coler 
HASA. Ames Research Center 

A shoi-t— term memory test device, the Response Analysis Tester (RAIEER) 
developed 1:^ General Eynamics, San Diego, was tised in the 90-day study. Prior 
to the selection of RMER, an extensive literature survey and an evaluation of 
availaTjle performance tests were made. 13?he goal of this effort was to locate 
tests of higher order functioning whitdi. cotild "be used to measiore performance 
in a wide variety of stress situations. Results of the survey indicated that 
RATER showed p2X>mise of providing a stahle sensitive test of one aspect of 
higher order functioning. 

RATER is shown in figure 1. The larger unit contains all the controls and 
indicators needed for administration of the test and collection of the data. 
This unit remained outside the test chamber. Only the small display and response 
unit was inside. TSae subject sat in front of this tinit and viewed the screen 
of a one-plane readout. A series of symbols appeared in a random sequence on 
the screen, your different symbols were used: triangle, circle, plus sign, 
and diamond, Tovac response huttons were located on the response unit, and each 
was associated with one of the four symhols. The subject's task was to press 
the appix)priate response button each time a symbol appeared. 

Two test conditions, delay and no delay, were used. The no-delay condition 
required that the subject respond to the symbol currently Iseing presented, and 
no short-term memory was involved. The delay condition required the subject to 
respond according to the symbol that had been presented two stimulus events 
prior in the sequence. Since all responses had to be delayed by two symbols, 
short-term memory was required throughout this test condition. The experimental 
hypothesis was that short-term memo3:y would be is^aired by the stress of con- 
finement. Thus, performance impairment was predicted for the delay condition, 
but not for the no-delay condition. 

Since only a small amount of RAOIER test data had previously been published 
(refs. 1 to ^), additional data were needed. TDo meet this need, a large group 
of male college students was tested in the Human Performance Laboratory at Ames 
Research Center. The resiilts of this test program were used in the selection 
of a set of test conditions for the 90-day study. 

Since most of the Ames laboratory subjects continued to show performance 
improvement over a large number of test sessions, and since asymptotic perfor- 
mance was desirable prior to confinement, 28 training sessions were specified 
for the 90-day study. A stimulus presentation rate of one symbol per second 
was selected. A two-symbol delay seemed to provide the desired level of dlffi- 
ctilty for the short-teim memory testing. Results of the laboratory study vere 
also xised to deteimine the minimum amount of data needed from each test session 
so that the sessions could be as brief as possible, but still provide adequate 
data. 



^^7 




For the 90-day study^ each test session consisted of a 1-minute warm-up 
test, a 30-second rest period, and then four 5-niinute test periods with a 
50-second rest period between tests - a total of 15 miniifces. The two test con- 
ditions, no delay (l) and two-symbol delay (H), were alternated over the fotir 
5-minute test periods in two ways: I-II-I-II (schedule A) and II-I-II-I (sched- 
ule B), For each subject, the two schedules were alternated over test sessions. 
The test condition (l or II) for the l-minute warniup was the same as the first 
3-mlnute test for any given session. 

Since the subjects co-uld make more than one response to each EATER, symbol 
presentation, performance was scored by subtracting the number of errors from 
the number of correct responses. Both of these values were read directly from 
counters on the control unit, and were recorded during the 50-second rest fol- 
lowing each test period. Immediately after recording each score, the exrperi- 
menter verbally reported the score to the subject. For each session, the 6 min- 
utes of testing on each condition at a symbol presentation rate of 6o per minute 
allowed a maximum possible score of 5^0. Warmup scores were not included in tlie 
data. 

Tha, test results are shown in figure 2. The set of cuiYes at the left 
shows the results for the training sessioirs prior to the beginning of confine- 
ment. The number of training sessions conrpleted varied among the fotir subjects 
as follows: 15, 19^ 22, and 28, Only the first 15 sessions are presented 
becatise performance of the three subjects who completed additional training 
neither Improved nor declined after the fifteenth session. 

Performance was very stable in the early days of confinement; a marked ^ 
inrprovement in the two-delay condition occurred between days 12^13 and l8,19. 
By the iBth and 19th days of confinement, the subjects had achieved almost per- 
fect performance for both test conditions. At this time, the subjects seemed 
to be losing interest in the testj thus a decision was made to increase the 
task difficulty, and thereby the challenge, by Increasing the symbol presenta- 
tion rate. With this Increase in the number of stlmul-us presentations, the 
maximimi possible score rose from J^Ojto ^0. After the rate change, tlie group 
mean for the two-delay condition began to decline, reached a very low level on 
the 28tli and 29th days, and then rapidly recovered. Unfortunately, during the 
same time period some test sessions were canceled for reasons unrelated to the 
EATER study, and other data were lost because of RATER malfunction. Thus, the 
group means for several sessions represent data for fewer than four subjects. 
For these sessions the number of subjects represented is shown directly below 
the session numbers in figure 2. (For example, ^2Bs means 2 subjectsj 2S32D 
means 2 subjects and 2 delays j ISHD means 1 siibject, no delay,) On the 33rd 
day of confinement, the test equipment failed. Despite efforts to have it 
repaired as quickly as possible, it was not restored to satisfactory operation 
until the 68th day. At this time, partly because the subjects had requested 
that the test be given less often and partly because additional apparatus fail- 
ure would mean another long, repair djelay, a decision was made to test only every 
fourth day rather than every other day. Wtien testing was resinned, the group 

' - ■'■ "" V . ' ■ ' ' ' ' ' ' ' 

*0n days 4 to 33 only two subjects were tested each day; thus, the group 
means represent data combined fram two consecutive days. 

11-38 



mean for the two-delay condition Tsegan at a rather low level but rose to reflect 
rather good performance toward the end of the study. 

lEhe performance decrements that haye "been discussed are not representative 
of the indlvld-ual performance of all suhjects. One subject had very substantial 
decrements which strongly Influenced the shape of the group ctirve for the two- 
delay condition. Figure 3 shows the test results, the data for that subject 
being raaoved. After the rate change, there is no largie decline in performance 
for the three subjects. However, it is obvious that the test had become more 
difficxilt and the subjects' performance never became as consistent or as close 
to the maximum possible score as it had been with the slower presentation rate. 
!Che decrCTients on day 75 are due, at least in part, to the fact that the values 
represent data for only one siibject. Because of an overs^lght, the other two 
subjects were xKJt tested at all on that day, 

While the 90-day confinement study was in progress at McDonnell Douglas, 
the authors of this report participated in a l4-day confinement study at the 
Tlniversity of Pennsylvania, For this study, six men were confined in a test 
chamber containing nitrogen enriched air (95^ K2) at a pressure of k atmo- 
spheres. The study was conducted in stippoTt of the !nEIE37IIE H Program, specif- 
ically in siipport of a proposed series of saturation dives at an undersea depth 
of 100 ft, 03ie presstire and gas composition of the Philadelphia chamber envi- 
ronment duplicated the expected conditions of the TEK3JITE program. 

Compa3?ed with the 90-day study, the Philadelphia study Involved a much more 
acute stress that had a specific physiological basis, This physiological stress 
was nitrogen narcosis, frequently experienced by divers, which produces symptoms 
similar to those of alcoholic Inebriation. Figure h shows the Philadelphia data 
(group means) plotted in a manner directly comparable with the 90-day data shown 
in figures 2 and 5. (in figure k, D denotes decompression and PEl and EE2 
denote past exposure of one and two subjects, respectively.} Again, the set 
of curves at the left shows the results of preco3Xflnement tralni33g. Compared 
with data from the 90-day subjects, the learning is more rapid and the curves 
are smoother and more stable. For the Philadelphia uo-delay condition, a rea- 
sonable extrapolation of the curve beyond the end of training wotild coincide 
with thfe act\]al confinement dataj no performance decrement is present. However, 
extrapolation of the two-delay curve would yield scores higher than those 
acttially achieved diiring the first days of confinement. This performance decre- 
ment lasted until at least the fifth day and indicated that the group perfor- 
mance wag adversely affected "b^ nitrogen narcosis, other conditions of the con- 
finement, or some combinations of these factors. 

On days 2 to ik of ths study, each stibject was tested twice: Once in the 
morning (approximately 7 to 9 a.m., denoted by a) and again in late afternoon or 
early evening (approximately 5 to 8 p.m., denoted by b). Normal diurnal varia- 
tions were eacpected to cause performance scores to be lower in the morning than 
in the afternoon or early evening, ^Dbe group means for each session were com- 
pared with thB means of the preceding session. Performance on the nd-delay 
condition remained high throughout the study, and no diu3-aal vaxiation was evi- 
dent. For tlie two-dele^ condition, the test did measure dlixmal group perfor- 
mance change in the expected direction at I9 of the 26 possible comparison 

^39 



points during the 1^-day confinement . Tbs 2.6 comparisons were then made for 

each subject individually, and these data for all six subjects were conibined in 

a chi square test. Q!he result is significant at the 1-percent level of 
confidence. 

A classical prohlem in evaluating the results of performance testing during 
long-duration confinement studies is that a failiire to observe decrements means 
either that there were no decrements due to the stress or that deci^ements did 
occxir "but the test instrument was not sensitive enough to measure them. Evi- 
dence supporting one eacplanation luther than the other is usually lacking. I!he 
reason for discussing the Philadelphia results is that hoth the performance 
decrements measured during the early days of confinement and the diurnal per- 
fonnance variations give evidence that the short-term memoiy test was sensitive 
to stress. Since a reasonable degree of test sensitivity has been demonstrated, 
it is probable that for tasks similar to the one described here, stresses such 
as those e2qperienced by subjects in the 90-'3ay confinement do not produce marked 
performance decrements. 

A troublesome fact, however, is that the performances for three subjects 
in the 90~day study were similar, but that of the fourth subject was substan- 
tially different and did show a decline during confinement. !Ehe deviant sub- 
ject's perfoimance had been quite good prior to the rate change, was i^asonably 
good on the first test session at the higher rate, and was followed by a precip- 
itous drop to an extremely low level for the two-delay condition only. Hie 
reason is not apparent from available records. It seems to have been caused 
either by a loss of motivation or, more likely, an -error in test procediire. 

An additional comparison of the 90-day study with the Hailadelphia study 
showed marked differences in tl;ie subjects' attitude toward the test. The 
90-day subjects' group rating for the study gave RAEER a desirability ranking 
of 40 in a list of 57 ItCTis (l - high, 57 = low). Ihii^ ranking was Judged to 
represent a "fair" level of acceptability. At the end of the Hxiladelphia 
study, subjects ranked the seven major experiment^ and the performance test 
received a mean rank of 2.5 • This re|ting occurred despite the fact that these 
subjects were given more test sessions and within a much shorter period of time. 
Two factors seem most important in accounting for the differences in accepta-^ 
billty: (l) in the Philadelphia test, the subjects actively competed among 
themselves for high performance scores throughout the study, -s&ereas such com- 
petition among the 90-day subjects was less apparent, and (2) most of the exper- 
iments in the Philadelphia ptudy were uninteresting for the subjects and some 
were also physically painftfl., whereas most aspects of the 90-day stvidy were 
less unpleasant. The Philadelphia subjects' better acceptance of the test prob- 
ably contributed to the more rapid learning and more stable performance seen in 
that study. 

The authors woxild like to use this test again in some future long-duration 
confinement study. However, three major changes would be made. First, testing 
would not be given moire often than once each week in order to encoiirage a more 
favorable subject attitude toward the test. Second, on those days Mhsn the test 
is given, a larger amoiaxb of data would be collected to improve the stability 



W> 



of nteasurement . Jtod tMrd, testing Trauld Tje given tvice on test days, once in 
the moming and again in the afternoon, so that dliraml -yBxiation ccmjarisons 
coxild "be made. 



KfclJj'KtCEiCiS 



1. Ibc^nch, R, S.: Assessiaent of Crew Efficiency: Hie Development of a Minia- 

turized RAiER, Model 5. Convair Report TTo. GDC-EKR-AN-II65, 15 December 
1967. 

2, Parker, J. W.i The Response Analysis Tester (RfflER) and IiOgical Inference 

Tester (n)GlT)i I, Some Preliminary Findings. U.S. l[aval Stibmarine 
Medical Center, Groton, Conn., Report Ho, 487, 2 February 1967. 

5. Parlser, J. ¥.: Tte Response Analysis Tester (RAIER) and Logical Baference 
TESTER (LOGIT)j H, Additional Pilot Study Diata. SDBIEDCEN Report 
Ho. 525, 17 May 1968. 



kkl 




Figure 1. - The Response Analysis Tester (RATER). 



k\2 



N = 4 



800 t 



600 



UJ 

cr 

3 400 



200 



PRESENTATION RATE 
1.0 sec per SYMBOL 



TESTING 
EVERY 
SECOND 

— DAY- 



PRESENTATION RATE 

0.T5 sec per SYMBOL 

TESTING 

EVERY 

FOURTH 

DAY 




\ 



\/\ 



NO DELAY 



/ 

V 



/,■V'^ 



TWO SYMBOL DELAY 

LEVEL OF PERFECT PERFORMANCE 



I I I I I I 



I I I I I I 



I 2 3 4 5 6 7 8 9 10 II 12 13 14 15 



6-i7 



J_ 



10-11 



14-15 



18-19 



22-23 



26:27 



30-31 



68 



76 



84 



4-5 8-9 1 12-13 16-17 20-2124-2528-29 32-33 72 I 80 I 8 



8 



3Sc 



3Sc 



TRAINING SESSIONS 



^ V 



ISND 2Ss 3Ss20 
3Ss 2Ss 2Ss2D 

DAYS OF CONFINEMENT — ^ 



Figure 2. - Mean performance of four subjects on the short-term memory test. 



iA3 



800 



600 



UJ 

q: 

g 400 



200 



N=3 
PRESENTATION RATE 

1.0 sec per SYMBOL 



PRESENTATION RATE 
0.75 sec per SYMBOL 



TESTING 
EVERY 
SECOND 

— OAY- 



TESTING 
EVERY 
FOURTH 
DAY 





NO DELAY 

TWO SYMBOL DELAY 

LEVEL OF PERFECT PERFORMANCE 



''''III 



I I I I I I 



I 2 3 4 5 6 7 8 9 10 II 12 13 14 15 



6-7 



10-11 



4-5 8-9 



14-15 



J_ 



18-19 



22-23 



26-27 



30-31 



68 



12-13 16-17 20-21 24-25|28-29 32-33 72 | 80 88 



J_ 



76 84 



± 



2Sc 



2Sc 



ISND IS 



-TRAINING SESSIONS 



V 



2S5 IS2D 2Ss2D 

— DAYS OF CONFINEMENT- 



^ 



Figure 3.- Mean performance of three subjects on the short-term memory test. 



khh 



N = 6 



400 




-^v^ 



\/ 



NO DELAY 



TWO SYMBOL DELAY 

LEVEL OF PERFECT PERFORMANCE 



la 



2b 



3b 



I I I 



4b 5b 



6b 



7b 



8b 9b lOb 



X 



lib 



± 



I2b 



j_ 



13b 



_L 



14b PEI 



8 10 2a 3a 4a 5a 6a 7a 8o 9a lOa lla I2a 13a I4a D PE2 
TEST SESSIONS 

Figure 4, - Mean performance of six subjects on the short-term memory test. 



1A5 



NON-INTERFERENCE PERFORMANCE ASSESSMENT (NIP A) 
By M. M. Okanes, Ph. D. , W. R. Feeney, Ph. D. , and J. S. Seeman 
McDonnell Douglas Astronautics Company 

SUMMARY 

Conventional psychological testing techniques (such as paper and pencil 
tests) which attempt to obtain social and emotional information have a history 
of negative reactions on the part of subjects exposed to them. One of the 
original goals of this program was to develop unobtrusive methods (in contrast 
to intrusive methods) of obtaining social and emotional data from crewmen on 
the 90-day Space Station Simulator (SSS) test by visually and aurally observing 
behavior. The object was to avoid the resistance produced by intrusive 
measurement and its concomitant effect on the data being gathered. 
However, unobtrusive observation means that crewmen must be completely 
unaware of observations being made. This was not possible because MDAC 
established the policy of giving as much information as possible to the crew- 
men about all aspects of the program. Thus, the title of NIPA is accurate in 
the sense that the program was conceived to be non-interfering rather than 
unobtrusive; i. e. , cooperation of the subjects was not required or desired. 
Although they would be aware that cameras and microphones are installed in 
the SSS, crewmen would be able to carry on their programmied tasks (and 
other behavior) without interference by the NIPA staff. The crew would also 
receive a number of intrusive tests of the paper and pencil variety. Ulti- 
mately the objective was to develop an observational methodology which would 
eliminate the need for intrusive testing methods where social and emotional 
data are desired in operational situations. Thus, MDAC views the NIPA study 
as a test of methodology and not as a means for contributing substantively to 
theoretical constructs in individual or social psychology. 

EQUIPMENT AND PROCEDURE USED 



Equipment 

An observer station for NIPA was added adjacent to the communications 
monitor position in the SSS operations room. The NIPA observer used the 
TV monitors at the communications console showing the chamber interior as 
picked up by five cameras in fixed positions onboard. In addition, an auditory 
capability was provided so that the observer could listen to the onboard 
microphones as well as intercom conversations between the inside crew and 
outside staff. By day 31a remote repeater station was constructed on the 
second floor of the space laboratory. It essentially repeated the video and 
audio capabilities of the initial NIPA station. Recordings by the NIPA 
observers at both stations were entered into a teletypewriter producing a 
punched paper tape compatible as a computer input (see fig. 1). 

1^7 




The audio capability for NIPA was actually completed during the first 
week of the test. It became immediately obvious that the system was not 
designed to the requirements for NIPA observations. Background noise in 
the chamber made it virtually impossible for the NIPA observer to hear what 
the crewmen were saying. Installation of audio filters and other circuit 
modifications were attempted outside the chamber. After a crewman lowered 
the microphone hanging over the table used for eating/recreation, it was 
concluded that satisfactory pickup of crew conversations could occur there. 
For the remainder of the test NIPA observers limited their observations of 
verbal data to that area. Despite these and later "fixes", the audio quality 
continued to tax the limits of observer auditory perception throughout the test, 
except for intercom conversations. A gross subjective judgment by NIPA 
observers indicates that about 60 percent of the onboard verbal interactions 
were understood and recorded. 

Additional equipment was provided in a room adjacent to the remote 
station to conduct observer reliability test and training sessions. Video tape 
recorders, TV monitors, and audio equipment made it possible to tape the 
information being presented to the NIPA station at any time. Thus, segments 
of crew action were recorded and established as stimulus standards for 
presentation in observer reliability test sessions (see fig. 2). 

Procedure 



The NIPA observer had to record three classes of information: 
(1) verbal interaction data, (2) the physical locations of crewmen with asso- 
ciated activities, and (3) other observer judgments. Intracrew verbal inter- 
actions as well as conversations with outside staff members were recorded. 

The observer identified and recorded who initiated and who received each 
interaction. In addition, he made a judgment of verbal content based on four 
categories derived from the 12 Bales Interaction Process* categories 
(see fig. 3). The observer's orientation was to assess the verbal content for 
the presence of emotional affect. He attempted to determine whether the 
receiver of the message treated the affect as positive (liking, approving, etc. ) 
or negative (disliking, criticism, etc. ). If no affect was detected, the 
observer classified the statement as either asking for information or giving 
information. Thus, if Terry asked information of Steve three teletypewriter 
keys (appropriately labeled for NIPA) were depressed in the order: QAW 
(see fig. 4). 

The physical locations of crewmen were recorded on the teletypewriter 
every 2- 1/2 minutes in terms of nine preselected areas in the chamber. In 
addition, certain specific locations were identified to indicate crew time on 
special equipment such as the Langley Complex Coordinator or actually 
watching the onboard TV monitor (see fig. 5). 



*Bales, R. F. Interaction Process Analysis , Cambridge, Mass.: 
Addison- Wesley, 1951, 



The NIPA observer was also required to record other assorted judgments 
including a subjective assessment of workload (labeled "task-press") on a 
seven-point scale and some psychosomatic complaints, if verbalized (see 
table 1). 

NIPA observers monitored crew behavior daily. For one period early 
in the test, monitoring was done continuously from 0700 hours until 0100 hours 
the following morning. However, manpower requirements made it necessary 
to reduce the monitoring time to the segments of time when four crewmen 
were up (i. e, , du:^ing nonsleep periods). This change was consistent with 
a pretest decision to place primary emphasis upon these periods. As a result, 
the data discussed here were collected daily during the hours 0600 to 1400 and 
2000 to 2400. 



DATA REDUCTION 



The data reduction effort for NIPA reduced large amounts of raw data to 
permit the testing of relationships among the psychological variables under 
study. As mentioned above, the raw data are measurements of crew behavior 
made on a continuous basis by observers looking at closed-circuit TV moni- 
tors which display the interior of the SSS. 

In general, the scheme employed two teletypes, one at the initial and 
the other at the remote observation station, to record the behavior of the 
onboard crew by audio and video links. Observers used the teletypewriters to 
produce a character "string" which is essentially a serial record of crew 
behavior. The string, recorded on paper tape, is read into a computer which 
in turn "reduces" the data into time intervals of 20 minutes, 4 hours, and 
1 day. The computer program can also produce a protocol. 

The NIPA flow is illustrated in fig. 6. Three distinct phases are shown: 
data collection, data reduction, and data analysis. The teletypewriter entries 
are coded observations of the crew which conform to the variables mentioned 
earlier. The teletypewriter had specially labeled keys which conformed to 
these variables. Paper tapes containing approximately 4 hours of observer 
entries represented the output of the data collection base. These paper tapes 
formed the raw data "string" to be reduced by the data reduction phase. 

Data reduction was done on a time- sharing computer. The raw data 
paper tape was read into a remote tape reader. The program produced a 
magnetic tape copy of the paper tape and a printout of the frequency matrices 
for each individual tape. These frequency matrices are directly related to 
each type of measure and provided the numerical values of the indices that 
were used in the analyses. 



\k9 



ANALYTIC TECPJNIQUES 

The most basic level of analysis requires statistical correlation and 
multiple regression analysis of the variables associated with NIP A and the 
intrusive (paper and pencil) test variables. Graphical presentation of data is 
also employed. Although a program exists to perform correlations, at present 
the NIPA data are not completely reduced to the point where data input can be 
made to it. Therefore, correlations are not available for presentation. 
However, at this writing data are summarized for a number of indices for each 
day of the run during four-man-up periods , making it possible to present some 
graphs showing group results (i. e. , not individual crewman results). It is 
emphasized that these results are based on a preliminary analysis of one data 
point for each day for each applicable variable and that analysis of the data in 
terms of 20 -minute summaries is in progress.. The data prior to day 31 in the 
graphs that follow should be considered unreliable because: 

A. From day 1 through 15, no data were gathered. 

B. From day 16 through 30, the NIPA observers and staff were learning 
the refinements necessary for the new data collection method. 

C. A number of ground rules or conventions were created or changed 
during that period affecting how typical or marginal cases were to 
be recorded. 

D. Observers were receiving their first training with the complete 
complement of NIPA equipment. 

RESULTS 



Figures 7 and 8 deal with verbalized emotional affect expressed in ratios. 
Verbal statements identified as containing affect were recorded as either 
positive or negative. The total number of positive and negative statements 
represents total affect for a given duration. The number of positive statements 
out of the total affect may be expressed as the positive affect ratio, as follows: 



S + 



Positive Affect Ratio 



(S + ) + (S - ) 
Similarly, 



Negative Affect Ratio = 



( S + ) + { S- ) 



450 



Figure 9 is a measure of the extent to which the crew members were 
geographically separated from each other. The ordinate is labeled psycho- 
logical distance. If one crewman is standing in the equipment quarters and 
another is in the crew quarters, they are separated by a measurable physical 
distance. However, if the bulkhead door separating the two is closed, the 
psychological distance between the crewmen is significantly greater than if the 
door is open. Therefore, a scale was developed to measure this and similar 
psychological distances between the areas shown on the floor plan in fig. 5. 

CONCLUSIONS 

The three graphs selected for presentation here show tentatively that the 
NIPA methodology is sensitive to changes in social and emotional states, 
especially at psychologically significant points during the test. Of interest is 
that not all the paper and pencil tests detected these changes. 

It is known that certain interpersonal problems existed among the crew 
from days 60 to 70. The positive affect ratio generally shows a dip during 
this period while the negative affect ratio shows a rise. Similarly, group 
dispersion shows a rise. These are all in the predicted direction as reflec- 
tions of interpersonal problems. It is expected that an even clearer picture 
will be presented when the data are graphed for individual crewmen and when 
our correlational analysis is complete. 

The fact that the NIPA method provides data on a continuous real-time 
basis provides advantages that become apparent in dealing with graphical 
data: (1) the data are sensitive to short-term changes and (2) events are 
detectable that occur between intrusive test admiinistrations. Short-term 
change detection might be possible with paper and pencil (intrusive) testing 
if administrations were very frequent. However, this is not feasible because 
of the following reasons: 

A. Crew reaction to being administered intrusive tests daily would 
certainly be negative. 

B. Timie and cost of test administration would not be justified. 



^4-51 



Table 1 
OTHER OBSERVER JUDGMENTS 



Category- 



Recording 



How Often 



Task- press/workload 

Bulkhead door, open or closed 

Complains of headache 

Complains of stomach upset 

Complains of fatigue 

Complains of depression 

Other complaints 

Problem- solving and creative/ 
innovative behavior 



Touch equipment 
Touch persons 

NOTE I: Recording scale as follows 
7 Scale 

1 Overwhelming - cannot be done 

2 Extremely heavy - can be done 

3 Moderately heavy - can be done 

4 Average 

5 Moderately light 

6 Very light 

7 No task requirement 

(This judgment is made from the 
crewman's viewpoint, ) 



7 scale 1 per hour 

Z scale Concurrently 

3 scale 1 per shift 

3 scale 1 per shift 

3 scale 1 per shift 

3 scale 1 per shift 

3 scale 1 per shift 

Concurrently 

Concurrently 
Concurrently 

3 Scale 

1 Not mentiojied 

2 Mentioned 

3 Severe 

2 Scale 

1 Open 

2 Closed 



NOTE 2: The requirement of one per shift is minimal. Additional 
recordings should be made as needed. 



452 







Figure 1.- Remote NIPA station. 






V 



















<,- 



Figure 2.- NIPA observer reliability test/training session. 



^53 



I r"i I 



^•g 



V) 



— CO 

o oc 



M 

UJ 

£ 
o 

UJ 

u 

M 

Ul 

-i 
< 

m 

UJ 



o ^ z 

cc £ o 

< 22 " 

S P «« 

UJ ^ Q 

OC M Z 

-^ ^ tr 

UJ o Is 

X E oc 

•is UJ 

«« «« S 

UJ — ? '^ 

^ SS z 



a u 



UJ 

u 

z 
< 



u 

u 



i» < 

ce -J 

111 • 

F UJ 

° g 

« 2 2 

<3 s; ^ 

-• Z M 

o UJ 7 

W H CO 

M M UJ 

^ I; UJ 

O O OC 

X X » 

CO CO < 



T- CM M 



CO 

■• 3- S 

OC CO X 

UJ MM X 

a -J CO 

U. Ut UJ 
V "' UL 

£ Ik X 
1 M K 

g UJ < 

O CO CJ 
H "J « 

^ O. H 
C9 UJ UJ 

5 2 uj 

> w tt 
.iJ > 

a. _j z 

S < O 

z'<g 

S z 1 

H- O K 

U — O 

UJ H- u. 

OC < Z 

9 _j T 

I < z 

5 > o 

O UJ r- 

UJ O z 

» i ^ 

3 ^ K 
CO o o 

M CO CO 

UJ UJ UJ 

> > > 

O C9 O 



«l> m <B 



z » 

O S 

S UJ ^ 

S u. Z 

tc ^;^_ a 

o a ^ 

CJ X u. 

5E a O 

5 £ S2 

lU »" SI 

S: M -' 

£ CO S 

z i ^ 

< g 
r- Z ~ 

5 < as 

1 z 5 

X O H 

o J- ej 

U. H- UJ 

2 < K 

T -J 5 

Z < I 

o > z 

[^ UJ O 

S O Ul 

S = C9 

^ X C9 

K CL 3 

O O CO 

K K X 



CO M CO 

^ ^ ■>< 

CO CO CO 

< < < 



UJ 

X 
CO 



UJ 
CO 
CO 

K 
UJ 

< 

O •• C3 
X Q CO 
X -J a 

h= uf Z 
S u. UJ 

* u. [J; 

>: o g 

3 9 SS 



O < 

u. OC 

z g 

fe S 5 

UJ «* 

!^ »J CO 

«= X S 

^ g =i 

g ^ s 

i s I 

i I z 



M 



a 



< o ^< 




w X ce K 




z b ^ z z u 

iiiiii 

S < z u z £ 




a > o Ul UJ UJ 




U UJ CJ O h- K 




U. U. Ik u. u. u. 




o o o o o o 




§ s s i s s 




CO 


l£j ill UJ UJ UJ UJ 


UJ 




K 


m ea BQ CD ea ea 


O o o o O O 


o 


K K X K K K 


(9 

UJ 



UJ 



3C ^ " 

£o E ca 

I CO < 

CO z I- 

uj lu z 

ju I- < 

I S S 

a CO CO 



^ C»4 



< 
u 

z 
o 

i 

Ul 

> 

z 
o 
u 

< 



■»' 


1 




UJ 

> 



« «» IS 

CO OC z 

Z UJ o 

< < Ul 

OC UJ g UJ 

— s P ^ 

I- iu to < 
2; b. UJ (9 

o E 2 SJ 
OL < d z 



o a 



0) 

-M 

O 

X3 



O 

(U 
CQ 

i* 
I— I 
I— I 

o 
o 

CO 
0) 

•rH 

o 

■3 
o 

1^ 

CQ 
U 

o 
o 

<: 



CO 



u 



J V, 



jo > 

uOJUm 
oS OC o 

(OUI < Oi 



)d < 1- 

COUJ 3 
<CC Ul 

I- < z 



I 



H < < 
O UJ C9 

_ S OC UJ 

CO Ul < Z 






k9^ 







G 

G 
G 
G 
G 
G 
G 
G 
G 
G 








s- 



1=' 





irj 








S 01 



© 









I 



p4 



u 

a 

.—I 

Is 
I— I 

no 
U 

I— I 
<0 



'Si* 



^55 

















o 






• 


O 
CM cr\ 


03 
O 

B 1 


\ > ^ 1 


m 


< 01 




P2 


^^" 


s 


= 1 


CD 


CM en ^ 
oo oo c 


z 2 


1 
1 
1 


o 
oo 




-OR l[ 

ed for 


1 ur\ 


O 



CD 

f— 1 
O 

:_-rL 


1 crs 


- 


.RVER 1 
.n label 


^ CM 


LU CQ 


^ 


1 DED TO THE 

simulator floo 




so ^ 

. CM 

i-H ^ 


> 
1 


^SABATIER 
REACTOR 


A LIST WAS PROV 

Figure 5.- Space station 


4 

CM 
O 


CM cn 

.— 1 I— 1 











i^56 




CO 




f-Ouu ^ 




O 

< 



o 

I— 
o 



o 
o 



< 



03 



o 
o 

U 

o 
a 

Qi 

r— ( 
1—4 
O 

ci 



o 



u 
o 

I— t 
I 

o 



1^57 




< 
o 

J— 

CO 



o 

i 

u 

-M 

o 

0) 

CQ 
O 
PM 

i 

(U 

•r-l 



OliVd 



458 




CD 



O 
OO 



s 







ci 






u 


o 




-4-> 

o 


ir\ 


>- 


,<u 




< 


4-1 




O 


Q 




1— 


>> 


§ 


CO 

LjJ 

1— 


!z; 

• 

00 

(U 






S) 



CM 



Pm 



OliVH 



i^59 




>- 
< 
o 



o 

•1-4 

CQ 
U 
Qi 
Oi 
03 



!■ I O 

o 



a* 
u 

•iH 



« 



s a s 

33NViSiaW3l9010H3ASd 



k6o 



PSTCHOLOGICM. ASSESSMEKD OF COHFUED CEE^ 

^ Barry E. Collins, Joan Ranere, 

and. Alvan Rosenthal 

University of California, Los Angeles 



INTRODDCTIOK 



Many of the hardware alarms during the 90-day run resulted from failures 
in measurement instrumentation, hut most of the engineering papers on the mis- 
sion have been ahle to rely on established, reliable, and valid assessment pro- 
cedures. In our assessment of the psychological and social integrity of the 
crew, however, the experiment is as much concerned with evaluating the meas-uring 
instrument as with evaluating crew behavior. 

Psychologists axe seldom subtle in their efforts to assess and categorize 
their human subjects. They ujsually require a subject's full attention and 
cooperation —whether fiUin^g out questionnaires, free associating, or manip- 
•ulating test equipment. But in a space mission, the psychologist who follows 
this precedent inevitably creates operational problems. He adds to the heavily 
scheduled workload of the crewman, and thus his tests generate frustration, 
antagonism, and a decrement in performance on essential operational tasks. 
"Konintrusive"^ psychological assessment (HIPA) would clearly ease the opera- 
tional problems for any crew, -s^ether in orbit or not. 

Even in other settingis, -wtxere psychological testing does not interfere with 
operations, the traditional, intrusive types of psychological measurement have 
come under recent criticism. At worst, these intrusive techniques alter the 
object being meastiredj the veiy fact that a subject knows he is being evaluated 
probably changes his thoughts, feelings, and behaviors. Furthermore, psycholo- 
gists are beginning to realize that these traditional, intrusive measuring 
instruments are subject to a number of biases such as social desirability, 
response sets, and evaltiation apprehension. The essence of the criticism seems 
to be that the subject tries to create a false instrument reading. He gives 
answers idaich he thinks the psychologist wants to hear rather than what he him- 
self feels to be true. lEhus, besides their operational advantages, nonintrusive 
tests may provide the most valid instruments for psychological assessment. 

It wotild have been tenrpting to use the HIPA study to provide a narrative, 
biographical account of the cr^w experience during the 90-day run. The events 
in the lives of the crewmen were certainly varied and interesting, and one is 
loathe to leave them unrecorded. But if the U.S. space program hopes to develop 
a scientific procedure for Identifying and forecasting problems in crew per- 
formance, we must abstract those parameters of crew behavieo: which are most 
predictive. It is for this reason that we decided to focus the NIPA obseiver's 
attention on the physical location of the crewmen, pl^sical movement, and on the 
task and affective aspects of their verbal communication. 



k6l 



CRUHRION PROBLEM 



]^ almost every measurement procedure established in advance of the 90-^8'y 
test, the crew performed at 100 percent. Although there had to he considerahle 
rariaace in behavior from crewman to crevman and from day to day, our performance 
gages did not register differences in the range of task perf oirmance that was 
ohserved. For instance, we carefully recorded the numher of required and recom- 
mended tasks completed on each day of the mission. We expected that, as the 
mission wore on, some of the tasks would not he completed on particularly horing 
or stressful days. The mission analysis log, however, indicates that essentially 
every task was completed every day, so that the measurements collected show no 
variance J they were "wrapped around the peg^' for the entire mission (fig. 1). 

As may he too often the case, what is -vAieat for the operational personnel 
is chaff for the hasic researcher aad long-range planner. If every day is clas- 
sified only as a "success," we have no index of which days were merely success- 
ful and which were extremely successful. In other words, we have no ve-riance 
in ovx criterion variable and hence no criterion variable to predict. The data 
collected in the ITEPA project may well represent some of the most sensitive and 
innovative predictive variables ever devised in this type of study, but there 
is nothing to predict. Thus, most of the data analyses are essentially "boot- 
strappiiig." We can intercorrelate the various IDIPA predictive instruments with 
other predictive instruments such as pencil and paper questionnaires, medical 
interviews, and the psychomotor tests on board the simulator. We can correlate 
all these variables with environmental variables such as temperature, htimidity, 
and noise levels. In short, we shall never know whether our predictive instru- 
ments could have spotted serious personal or interpersonal difficulties before 
they created a serious problem for operations becatise the kinds of problems we 
would like to be able to predict were conspicuously absent from this 90-day test. 

THE AOTOCORRElIiAIDIOK TECBNIQUE 

Traditional methods of psychological analysis attempt to discriminate among 
subjects, and the traditional form of correlation would predict which crewman 
would be likely to perform best, which second best, and so forth. With only 
four crewmen, however, this type of analysis is inappropriate. Thus, a crew of 
four does not provide a large enough statistical base to make reliable, statisti- 
cal Judgments on crewman evaluation and crewman selection. 

However, since the crew did spend 90 days aboard the simulator, we can 
study the covariation among measures across time — ofiien called the autocorrela- 
tion technique. Conclusions from these analyses are relevant to problems which 
arise after the crewmen have been selected. The generalizations which will hope- 
fully emerge from these data analyses will help tis to detect personal and inter- 
personal problems which occur after a crew has been selected and has started 
work on the mission. We can look for nonintrusive correlates of fatigue, frus- 
tration, boredom, and psychological tension through time. (See fig. 2.) 



k62 



im. PREDICTOR YAEilABLES 



We made a ntmiber of .sinrplifying assxnnptions for this first illustratlTe 
data analysis. First, we focxised on. those periods diaring the day in -which none 
of the four crewiien vere scored as sleeping. Secondly, we focused on changes 
tha.t occtirred from day to dayj we generated a single ntmiber for each crewman 
per day to summarize his activity for that day. furthermore, we have limited 
our initial attention to events that occurred after day 51 — the day on •vdiich 
the TJCLA. ohservers went on-line at the remote observing station. 

Uius, for each crewman we have a number for each of the last 6o days sum- 
marizing the daily activity during periods in which all four crewmen were not 
asleep. A measure of privacy was obtained "by scoring the percentage of spatial 
ohseirations in iidiich each crewman was alone in one of the coded physical areas 
of the simulator. We have a measure of physical dispersion which reflects the 
total distance of one crewman from the other three crewmen. Ihere is a measure 
which reflects the average length of movement -idien a crewman mywes from one area 
of the slurulator to another and anther msasure of physical activity which 
simply reflects the total nxsmhev of movements made during the observed period. 

Each 2.5 minutes, when the observer noted the pliysical location of a crew- 
man, he also indicated in which of nine activities that crewtoan was engaged. 
We can get a rough index of time spent working on tasks by computing the per- 
centage of all ^udgnoents which were coded as task activity. From the commxmica- 
tlon monitors' log and from on-line observation by mission analysis personnel, 
we have a figure representing the total number of times a, crewman was asked to 
perfoim a task during time scheduled as free time or recreation in the time 
line. From the same source we have a measure of the duration or amount of time 
spent on the tasks described above, 

KESUIiTS 

The thi^e task variables are Intercorrelated. (See fig. 5«) Time on task 
correlates (^.26 with intrusions and 0.^7 "with duration. Intrusions correlate 
0.68 with durations, Biese three task measiares represent, operationally, two 
independent measurement procedures. The HIPA observer on the remote station 
judged every 2.5 minutes whether or not a crewman was engaged in task activity. 
Independently, down in. the control room, the communication monitor recorded in 
his log, or a mission, analysis observer recorded in his, the ntmiber and dtiration 
of requests for task activity during scheduled recreation tlm.e, QSius, these 
correlations among the task measiires are not trivial because the intrusions and 
durations data were collected at the control station by the Gommunicatlons 
monitor and mission analysis personnel, whereas time-on-task measurement repre- 
sents the cumulative judgments of the ITOLA. trained UPA observer at the remote 
station. These correlations serve to validate the reliability and validity of 
both the MIPA observers and the data, reduction process. 



1^65 



THE SEABGff FOR A NOIEEADTIVI CKEEEEilON OF CREW EERFORMfiHGE 

ThB fact that the crew performed at 100 percent on all our measures of 
task performajice illustrates the reactive nature of these intrusiTe measure- 
ments. DJhe crewmen were aware that operatloiaal personnel were assessing irtxether 
or not they completed all the recommended and mandatory tasks. !Bae crew's 
knowledge that they were being evaluated in this manner also contributed to the 
fact that they completed all tasks every day. 

Postegress interviews with the crewmen indicate that they did feel that 
their performance varied considerably from day to day — even though this varia- 
bility in task perfarmance was not reflected In any of the reactive measures- 
set up before the 90-day run. But are there any residues of their performance 
remaining at the end of the 90-day run which might reflect this vmdetected 
variance? Ideally we would want to find some regularly scheduled meter reading^ 
dial adjustment, or other activity which required some degree of perceptvial, 
mental, or motor ability and atteiition to accoi^lish. Furthermore, this would 
have to be an activity on which tha crew did not expect to be evaluated. If 
our speculation is correct, the crew was motivated ta perform at maximum on 
those variables monitored by the off -board crew. 

One daily task -v^ich coxild be examined is the daily computer feedout by the 
crew. This output was monitored only for content, but variance in typographical 
quality is highly likely. The con^iuter, however, was not programed to note such 
initial errors and only recorded the final corrected message. Furthermore, the 
data link between the simtilator and the computer appears to have added a certain 
amount of noise to the transmission, which might be hard to differentiate from 
crewman error. Finally^ the software of the computer cleaned up some typographi- 
cal errors before the data were stored. 

An alternative and comparable possibility would be to look at the quality 
of the entries in the diaries of the individual crewmen. This is probably an 
intellectual and motor performance which varies in amount and qxiality. Soviet 
space scientists (ref . l) have exHmined the handwriting of cosmonauts during 
space flight. German scientists (ref. 2) report deterioration of fine motor 
movements in handwriting as a function of noise levels. The privacy of the 
crewmen can be respected if we ignore what is said and focus on style of expres- 
sion. Thus we might look for grammatical errors, crosscuts, poor penmanship, 
incomplete sentences, number of abbreviations, and so forth. Joan Ranere, the 
training director for UCLA on the 90-day test, devised and quantified 11 such 
variables for each of the last 60 days of the mission. Correlational and fac- 
tor analyses of these indices for each crewman indicate that several of these 
qu£intifiable writing factors vary together from day to day over the last 6o days 
of the test. In particular, three of the variables seem to form a reliable 
index for each of the four crewmen which may represent assessment of the intel- 
lecttml, perceptual, and motor acuity of the crewmen. Percentage of abbreviated 
words, percentage of inconrpleted letters, and percentage of incoioplete sentences 
are significantly intercorrelated for each of the four crewmen. (See fig. 4.) 
It should be stressed that these three measures represent distinctly separate 
aspects of writing. Incomplete letters involve only penmanship, a motor ability; 



abbreviationB are a form of shortlaand; incomplete sentences are grammatical, 
stylistic, and syntactical. For example, tising inconrplete sentences does not 
imply that the author will ahhreviate his words. Ihe fact that these three 
measixres are intercorrelated for all four crewmen gives us some confidence that 
the q_tml.ity of the transcriptions in the diaries does indeed reflect a nonin- 
trusive intellectual, perceptual, and motor performance assessment. 

Before the 90-day test, most of us anticipated that confinement, stress, 
and hardware crises would constitute the greatest threats to psychological and 
social integrity. We predicted that performance would deteriorate on those days 
with a heavy task load and/or poor environmental quality. 

TJCLA personnel who monitored the run formed a quite different clinical 
Impression a little more than halfway through the run. It was our inttiition 
that the ma^or problem confronting the crew was horedom. If it is indeed "bore- 
dom, lack of novelty, and sensory deprivation which created the greatest prob- 
lems for psychological and social integrity among the crewmen, then we would 
expect jie greatest decrements in intellect-ual, perceptual, and motor ability 
on those, days when the task load was lightest , 

!I3aus, these different intuitions about the sources of trouble for the crew 
make different predictions for the relationship between task load and perfor- 
mance on our unobtrusive measure of mental and motor acuity. The crisis- 
fatigue-stress model predicts a negative correlation between task load and qual- 
ity of diaiy transcriptions; the boredom model predicts a positive correlation 
between task load and quality of diaiy transcriptions. (See fig. 5.) 

The data suggest the boredom model. All three of our measures of task 
pressure are positively correlated with transcription quality. It was on the 
days that the crewmen were most harassed by task demands that they used the 
fewest abbreviations, recorded the fewest incomplete letters, and transcribed 
the fewest incomplete sentences -■ that is, were most careful and complete in 
their diary entry. Accordi3ag to this measure of task performance, the crew was 
at its best when the task load was heaviest. 

This interpretation is supported by the fact that transcription quality 
tends to increase on days when the crew took long trips around the simulator. 
All six correlations among our two measures of length of movement and the three 
transciption quality indices are positive and range from 0.09 to 0.5^. Again, 
it appears that crew performance was at its best when they were most taxed. 



11-65 



REJFEREHCES 



1. Altukhov, G. V.} et al.: Issledovanle Pdcherka pri Pis^me v UsloviiaMi 

Kosmlcheskogo Poleta. Zhumal Vysshei Nervnol Delatel'nosti, vol, 1^, 
no. 5, 1965, pp. 865-868. 

2. Jansen, Gerd; and Hoffman, Helmut: Larmbedingte Anderungen der Felnmotorik 

und Lastigkeitsenrpf indungen in AbhSngigkeit von TDestimmten 
PersSnlichkeitsdlmensionen. Zeitschrift fur Experimentelle und Angevandte 
Psychologie, vol. 12, no. k, 1965, pp. 594-615. 



If66 



CALIBRATION OF PERFORMANCE MEASUREAAENT 



Potential Ranges 
of Crew 
Behavior 

Extremely Successful 

Very Successful 

Moderately Successful 

Acceptable 

Poor 

Failure 



Observed Range 

of Crew 

Behavior 



Calibration of 

Performance 

Assessment 

nstrumentation 



Figure 1. 



AUTOCORRELATION 

Traditional correlation: Covariance between variables across a number of individuals 

CM 4 



Predictor 



CM 3 



CM 1 



CM 2 



Behavior 
Autocorrelation: Covariance between 2 variables across a number of times 

Day 90 



Predictor 



Day 2 



Day 3 



Day 1 



Behavior 
Figure 2. 



k67 



CORRELATIONS AMONG TASK VARIABLES 



UCLA NIPA 
Observer at 
Remote Station 



AADAC Observers 
at Communication 
Monitor Station 



1. Time on task 

2. Task intrusions 

3. Duration of 
intrusions 

Figure 3. 



26 



47 .68 



CORRELATIONS 
AMONG ASPECTS OF DIARY TRANSCRIPTIONS 



(1) Abbreviations 

(2) Incomplete Letters 

(3) Incomplete Sentences 





Crewman 
1 


Crewman 
2 


Crewman 
3 


Crewman 
4 


(1) & (2) 


.34 


.12 


.67 


.36 


(1) & (3) 


.16 


.06 


.30 


.35 


(2) & (3) 


.21 


.23 


.44 


.38 



Figure 4. 



468 



CORRELATIONS BETWEEN TRANSCRIPTION QUALITY 
AND TASK LOAD 



Time on Task Duration of Intrusions 
Abbreviations -.36 -.10 

Incomplete Letters -.19 -.09 

Incomplete Sentences -.21 -.30 



Figure 5. 



k69 



BEHAVIORAL ACOUSTICS - THE IMPACT OF SPACE 
SIMULATOR NOISE ON CREW MEMBERS 

By Lawrence E. Langdon, Richard F. Gabriel, 
and Paul A. Abell 

Douglas Aircraft Company 
SUMMARY 



A multi-faceted program was used to evaluate the effects of Space Station 
Simulator background noise on the crew members. The main goal was to 
define limits for the background noise in future long-duration missions. 

A 1/E-hour behavioral acoustics test battery was given to each crew 
mLember weekly. Two of the crew members showed some temporary reduc- 
tion in hearing acuity during the 90-day test. One of the crew members 
became sensitized to the quality of the simulator background noise near the 
end of the test. No important changes were seen in speech comprehension. 

Repeated habitability questionnaires, a post-test questionnaire on noise, 
and a noise debriefing were used to obtain crew reactions. The living quar- 
ters noise, approximately 64 dB(A) (NCA-55), was rated reasonably satis- 
factory. The equipment area noise, approximately 7? dB(A) (NCA-70), was 
not well accepted, although crew m.embers spent limited time in that area. 
Intermittent noises such as pumps and talking were rated as the worst noise 
problem, especially when trying to sleep. 

Specific recoramendations based on these findings and assessment of the 
adequacy of the acoustics test program are provided. 



INTRODUCTION 



Nornmal background noise limits are of questionable validity for long- 
duration space missions because most standards are based on an 8-hour/day 
exposure and because there may be interactions between noise level and 
reduced cabin pressure. Furthermore, some temporary reduction of hearing 
acuity was noted in earlier studies (ref. 1). 

Noise- reduction goals were established for the design of the simulator, 
which consisted of a living quarters area, which had a noise level of approxi- 
mately 64 dB(A), and an equipment area, at approximately 77 dB(A). The 
basic function of the behavioral acoustics program was to provide information 
for future ambient noise specifications by asking the following questions about 
the present program.: 

• Were there changes in absolute hearing acuity (threshold) during the 
conduct of the test? 

471 




• Were there changes in speech comprehension? 

• Did subjects habituate or become sensitized to the cabin noise? 

• What were the crew's attitudes toward the noise? 

PROCEDURE 



Cabin Noise Measurements 

Cabin noise was measured before the 90-day test and three times during 
the test. In each case, the noises at numerous locations were recorded using 
a calibrated tape recording system. The recordings were analyzed to deter- 
mine the frequency spectra and levels (amLplitudes) of the noises. This work 
is discussed more fully elsewhere (ref. 2). 

Behavioral Acoustics Test Battery 

A three-part behavioral acoustics test battery was given twice before the 
90-day test, weekly during the test, and twice after the conclusion of the test. 
All tests were presented through circum.aural earphones, which attenuated the 
background noise. A pushbutton was provided for crew memiber responses. 

The audiometric test consisted of presenting each of six tones (5 00, 1,000, 
2,000, 3,000, 4,000, and 6,000 Hz) to each ear separately. The crew m.ember 
pressed the response button when he could not hear the tone and released it 
when he could hear it. This actuated a motor-driven volurae control which 
adjusted the level. The level was continually recorded on a chart, providing 
a tracing of the crew member's hearing capability. 

Speech interference tests consisted of a series of words miixed with 
recordings of the simulator ambient" noise. The crew member used answer 
sheets containing sets of six rhyme words and checked the rhyme word in 
each set which he thought he heard. Two types of tests were given. In the 
first, 50 different rhyme word sets were used to provide a varied saraple of 
speech. The second used the same rhyme word set repeatedly to provide 
maximum reproducibility of the data. Each of these tests was given twice, 
mixed with recorded living quarters noise and mixed with recorded equipment 
area noise. In each case, preliminary tests completed before the 90-day test 
were used to set the speech level at a point w^^here approximately 50 percent of 
the words would be recognized correctly. This increased the sensitivity of 
the tests. 

The acceptability or annoyance tests were adaptations of the loudness and 
annoyance judgment techniques used in rating aircraft flyover noises. Crew 
members listened to pairs of noises presented serially. A standard sound 
(random noise filtered to contain equal energy in each octave) was followed by 
recorded simulator noise. The crew member pressed his response button 
once if he preferred the first noise, twice if he preferred the second. After 



presentation of each pair, the experimenter adjusted the standard noise level 
based on the crew member's responses, so that he could determine the level 
judged as acceptable as the cabin noise. This test was also given twice, once 
with living quarters noise and once with equipment area noise. 

Assessment of Crew Attitudes 

A habitability questionnaire was given biweekly during the 90-day test. 
Crew members rated 58 environmental factors on a scale of excellent, good, 
fair, or poor. Three of these items related to noise levels. The questionnaire 
thus provided absolute ratings of noise adequacy as well as a comparison of 
crew assessment of the noise and their reaction to other factors. The ques- 
tionnaire is discussed more fully in reference 2. 

The day after leaving the chamber, an extensive debriefing was conducted. 
Approximately 15 minutes of this debriefing were sjient on noise. The 
approach was to ask general and nondirective questions to facilitate spontane- 
ous crew comm.ents. 

The second day after leaving the chamber, the crew memibers were given 
noise questionnaires. These were used to obtain detailed and specific infor- 
mation about the noise levels, behavioral effects of the noise, crew judgments 
of the adequacy of the noise levels for future long-duration missions, and 
reactions to the behavioral acoustics test battery, 

RESULTS 



Behavioral Test Data 

Examination of the audiometric data suggested that they be summarized in 
six categories: loss (tw^o crew members) versus no loss (tw^o crew members) 
and low (500 and 1, 000 Hz), medium (2, 000 and 3, 000 Hz), and high (4, 000 and 
6, 000 Hz) frequencies. Figure 1 shows the audiometric data grouped in these 
categories. Average levels for loss and no-loss groups were somewhat dif- 
ferent because one crew meraber in the loss group showed hearing loss 
at a consistently higher level than the other three crew members. The curves 
for loss and no-loss groups were therefore adjusted, equating pre-test levels 
to facilitate comparisons. 

The no- loss group showed no significant hearing loss during the 90-day 
test, but did show^ pre-post differences. The loss group showed a nearly 
linear increase in loss over the 90 days, but their pre-post changes are almost 
identical with the no- loss group. 

Figure 2 shows typical results for the speech comprehension tests. No 
trends were noted here, indicating that no degradation in ability to compre- 
hend speech occurred during the test. 



hj3 



Figure 3 displays typical data for the acceptability test^. Three of the 
crew members showed no significant changes. The fourth member found the 
simulator noise less acceptable as the test progressed. The further 
decrease in acceptability after the test was not expected but seems reason- 
able. It would suggest that the crew member disliked having to listen again 
to the Tonpleasant noise. The crew member who showed this sensitivity 
also reported the most dislike of the cabin ambient levels. 

Acceptability matching and speech conaprehension test results were of 
only rainor importance. Although one subject showed sensitization to the 
cabin noises, he had also reported dislike of the noise environment during 
his subjective evaluations. There were indications of communication diffi- 
culties during the 90 -day test, but the absolute level of difficulty in real 
communications could not be derived from the tests used. 



Audiometric results were difficult to interpret. Week-to-week vari- 
ability was large enough to obscure important changes in individual data, 
requiring consolidation of the data into six summary groups. Since the no- 
loss group showed the same change from pre-test to post-test as the loss 
group, it is probable that these changes are at least partly artifacts and 
that no real pre-post changes occurred (i.e. , the two subjects showing 
changes returned to normal by the first post-test). The second post-test 
showed even more loss than the first, and this strongly suggests that the 
changes result from decreases in motivation. Of all the behavioral acous- 
tics tests administered, the audiometric tests should be used during future 
tests and missions, since they are relatively simple to inaplement, can be 
self-administered, and yielded the only important changes. However, 
sources of week-to-week audiometric variation should be studied in greater 
detail. Two possible causes are intermittent noise and earphone placement. 
The problem of assessing or minimizing the effects of change in motivation 
will require additional study. Many audiometric techniques, especially 
tracking methods as used in these tests, have been developed or adapted to 
minimize gross problems such as malingering. However^ with a coopera- 
tive individual such as an astronaut, the problem is a much more subtle one 
of concentration and degree of involvement with the task. Furthermore, the 
amount of change of interest for these studies is much smaller than when 
screening for large hearing losses. 

Subjective Data 

Data from the habitability questionnaire, post-test questionnaire, and 
debriefing were very similar and give high confidence in the results. The 
crew members found the 64-dB(A) crew quarters noise quite reasonable, but 



kjk 



disliked the 77-dB(A) equipment area, even though only a portion of their 
time was spent in the equipment area. There was agreement that the 77-dB(A) 
equipment room ambient noise would be unacceptable for living quarters. 
There were complaints about intermittent noises, such as pumps cycling on 
and off and crew activities including talking. These intermittent noises 
mainly interfered with sleeping. There were comiments on some communi- 
cation difficulties evidenced by the need to repeat statements during both 
conversations among crew members and communications with the simula- 
tor control room. '■ 

Crew evaluation of the behavioral acoustics tests indicated a concern 
for the length and repetitious nature of the tests and for the distracting inter- 
mittent noises. The audiometric test was liked best and the acceptability test 
least. Subjects were aware of the week-to-week repetition of the word lists 
for the speech comprehension tests and believed that this naight have influ- 
enced their answers somewhat. 



CONCLUSIONS 

The following conclusions were reached regarding the effects of simu- 
lator ambient noise on the crew members: 

• Two of the four crew members experienced some hearing loss. 
Recovery apparently occurred during the post-test period. 
Random variation between weeks prevented a detailed description 
of hearing patterns. 

• Only one crew member showed a trend of acceptability change 
toward increased sensitization or annoyance with the simulator 
noise levels. This crew member showed even more dislike for 
the cabin noise during post-tests and reported the most subjective 
dissatisfaction with the cabin noise. This result suggests that 
selection of crew members for long-duration missions should 
consider this factor. 

• The speech comprehension tests showed no consistent significant 
effects. 

• The attained levels of NCA 55 and 70 [64 and 77 dB(A)] were 
close to minimum-desired and maximuna-tolerable noise levels. 
The difference between NCA 55 and 70 represents a clear and 
important change in acceptability. 

• Intermittent noises were a meaningful source of dissatisfaction, 
especially when trying to sleep. 



iH5 



Based on these conclusions and an analysis of the adequacy of the testing 
program, the following major recomimendations are offered: 

• Audioraetric monitoring during extended simulations or missions 
would be desirable. 

• Efforts should be made to increase the consistency of audio - 
metric data. 

• Future acoustic tests could be limited to audiometry without 
losing much information. 

• The NCA 55 and 70 attained levels appear to be reasonable for 
future minimxjm standards. 

• Additional reduction of the equipment area noise by at least 5 dB 
or reduction of time required in the equipment area wovild be 
desirable but probably not critical. 

• An effort should be made to reduce intermittent noises, such as 
ptamp noise, door noise, and talking, especially in the sleeping 
quarters, or to eliminate their intrusion upon sleeping crew 
members. 



REFERENCES 

1, Anon.: 6o-Day Itonned Test of a Regenerative Life Support System With 

Oxygen and Water Recoveiy. Pt. II - Aerospace Medicine and lSaxi-Ma.ch.lne 
Test Res-ults. DAG 62296 (Contract MS-w-l6l2), McDonnell Do-uglas 
Astronautics Co., Dec. 1968. (Available as HASA CR-985OI.) 

2. Seeman, J. S.j Singer, R. V. j and McLean, M. V.: Habltability. Prelim- 

inary Results From an Operational 90-Day Manned Test of a Regenerative 
Life Support System, HASA SP-261, 1971, pp. 593-^1^. 



kjS 



AUDIOMETRIC DATA IN SUMMARY CATEGORIES 




4 AND 6 KHZ 

Figure 1 



Of 

o 



o 



90 
80 
70 
60 
50 
40 
30 
20 
10 




INDIVIDUAL REPEATED WORD SET 
SPEECH COMPREHENSION DATA 



n — c 

1 


o 

A 

o 

n 


CREWMAN 1 
CREWMAN 2 
CREWMAN 3 
CREWMAN 4 




1 


,TO<v 


^^'J^^^^^^\^><(^^y\^^\_^ 


...J — 1 — I 


/ v\ \ x^ V ^^ 


/ ^^!>0<^ /X'Xv A 


II 1 1 III 1 1 



6/8 6/9 6/20 6/27 7/4 7/18 7/25 



8/1 8/7 
DATE 



8/8 8/15 8/22 8/29 9/5 9/12 9/17 



Figure 2 



477 



INDIVIDUAL LOW AMBIENT ACCEPTABILITY DATA 



80 

u. 

2 75 

UJ . 

^oa 70 
^»f 65 

Q S 

t^ o- 55 
o 

=3 



50 



45 



o 


CREWMAN 1 


A 


CREWMAN 2 


o 


CREWMAN 3 


a 


CREWMAN 4 




1 




6/8 6/9 6/20 6/27 7/4 7/11 7/18 7/25 8/1 

DATE 



8/8 8/15 8/22 8/29 9/5 9/12 9/17 



Figure 3 



kj8 



EEG MONITORING/SLEEP STUDIES 
j^ R. D. Joseph, W. B. Martin, and S. S. Viglione 
McDonnell Douglas Astronautics Company 

SUMMARY 

The 90-day test program provided for the acquisition and analysis of 
EEG and EOG recordings taken from 39 nights of sleep divided between two 
subjects. Approximately 350 hours of data were acquired and analyzed. 

Equipment required for collecting, mionitoring, and recording of the EEG 
and EOG was selected. All items to be maintained within the Space Station 
Simulator (SSS) were screened for toxicity, flammability, and electric shock 
hazard in compliance with the NASA safety program. 

A data collection and monitoring station consisting of telemietry receivers, 
tape recorder, and chart recorder was installed in the vicinity of the simulator. 
The station was located to minimize interference with operation of the support 
facilities. A reliable physiological telemetry link between the test crew and 
the recording station was established. 

An automatic scoring system was designed for each of the two subjects 
participating in the sleep studies. Six classifications are provided: avake, 
i^pid eye movement (REM), and stages 1 through k, as defined "by the Association 
for the Psychophysiological Study of Sleep (APSS).-^ In addition, movements and 
artifacts were also detected. 

The crewmen were indoctrinated in the role of the EEG and EOG 
recordings and trained in the methodology of preparing themselves for die 
EEG and EOG recordings. The importance of proper electrode attachment 
technique and correct electrode placement was stressed, since tiie quality of 
the EEG data is dependent upon proper homologous positioning and achieve- 
ment of minimum resistance from tiie scalp to scalp positions. An electrode 
resistance tester was included for this function. The crewmen were also 
trained in the use of the telemetry and the scheduling of the recording sessions. 

Recording during the 90-day manned test was in accordance with the 
protocol established in the data collection plan. A trained technician initiated 
and monitored the recording sequence, znaintained a data collection log, and 
noted unusual circumstances. He also monitored (from outside the SSS) the 
crew's preparation efforts and noted the effectiveness of electrode application. 




kl9 



The sleep scoring system, developed and validated on baseline data, was 
applied to the sleep recordings collected during the 90-day test. In addition 
to detailed printout of sleep stage classifications, the following is also pro- 
vided for each overnight record. 

A. Graphic representation of sleep stage occurrence 
(sleep print). 

B. Duration of each major sleep stage period and summary 
of total ainount of time spent in each sleep stage, ratio 
of time spent in various stages, number of transitions 

between stages, number of movements, In all, 

forty five (45) parameters were extracted from the 
daily sleep information for each subject to attempt to 
obtain a measure of the "quality" of the sleep. These 
parameters and the results are discussed further in 
the text. 

C. Plots of energy within specific bandwidths (e.g., delta, 
sigma) as a function of time. 

INSTRUMENTATION 



Two biotelemetry transmitters were placed in the chamber. They 
provide a pulse width-frequency modulated signal at approximately 88 MHz 
containing four multiplexed channels of data. Only one transmitter was used; 
the other was kept in reserve. A signal source in the chamber provided an 
82-microvolt, 5-Hz square wave for calibration. The calibrator box contains 
a circuit which measures the resistance of each pair of electrodes after 
application. 

The receiving antenna and lead wire were an insulated piece of wire 
strung along the chamber wall dropped from the ceiling. Outside the chamber 
this wire mated with a shielded wire which led to the data recording station. 
The demodulated data (two channels of EEG and two of EOG) were recorded on 
tape and simultaneously displayed on a chart recorder. Three of the recorded 
channels were read back immediately and also displayed on the chart recorder 
to ensure proper operation of the recording system. A time code generator, 
synchronized with one in the control roorn, produced IRIG B signals which 
were also recorded on tape and a binary output for display on the chart 
recorder. 

Placement of EEG and EOG electrodes followed the recommendations perti- 
nent to sleep research and published by the National Institute of Health. 1 



480 



A log book was maintained for recording data pertinent to the sleep 
recordings, particularly regarding artifacts, comments b the crewman con- 
cerning attitude, subjective evaluation of his sleep, naps taken during the day, 
and other pertinent information. 

SELECTION AND TRAINING OF PARTICIPANTS 

All four crewmen participated in a training session on May 27. Topics 
discussed included the collection of EEG. and EOG data as information pertinent 
to sleep stage identification, sleep research in general, objectives of this 
project in particular, operation of the telemetry system, application of 
elejCtrodes, and also typical checkout and calibration problems. Each crew- 
man received a pamphlet listing materials to be used, procedures for operation 
of telemetry, electrode application, and electrode evaluation. Each crewman had 
an opportunity to apply electrodes to the other, to learn the placement of elec- 
trodes, operate and calibrate the telemetry, and observe the resulting EEG 
during various conditions such as eyes open, eyes closed, alertness, and 
resting. All participants showed significant interest in this study and were 
able to obtain a good, clean recording. 

Two crewmen were selected on the basis of EEG data recorded during this 
session, the criterion being a relatively high level of alpha activity. A board- 
certified neurologist (Dr. Barbara Jensen, Newport Beach, California) 
compared this remotely obtained EEG with the clinical EEG done in her 
laboratory and concurred with the selection. 

BASELINE RECORDING SESSION 



For the purpose of obtaining baseline sleep information from the selected 
participants, the two selected crewmen were instrumented for recording on 
June 7 and 8 between 2300 and 0630. Both crewmen slept in hospital beds 
(adjustable) placed in a roomi at Astropower Laboratory, Each applied elec- 
trodes to the other (under supervision) and tested performance of the equip- 
ment; this was done in a separate room, removed from their sleeping quarters. 

The Pattern Recognition Group personnel monitored and documented tifcie 
recording sessions. Two outside consultants (specializing in sleep research) 
(Drs. L. Johnson and P. Naitoh, San Diego College) participated in the first 
night's recording, made final decisions on electrode placement, evaluated the 
first hour of recording, and the next day participated in initial sleep scoring 
(using the manual- visual inethod). 



kQl. 



DATA COLLECTION 

Three periods of data collection were scheduled: days 1 through 10; 
days 42 through 46; and days 85 through 89. 

Data collection was begun on the first day at 2300, the time of the first 
scheduled sleeping period for the crewman on the unaltered sleep cycle. For 
various reaso^R, no recordings were made of the other crewman until his third 
scheduled sle ing period. Data were taken during 10 consecutive nights for 
the former and 9 consecutive nights for the latter. 

A procedure was established for checkout and calibration of the tele- 
metry, installation of fresh batteries, application of electrodes, and comxnuni- 
cation between crew^men and monitoring personnel. 

Availability and cost of chart paper made it possible to record only the 
first two sessions from each subject at a speed which permits manual scoring 

of sleep. For the rest of the sessions the paper was run just fast enough to 
check the quality of recording and read the time code for later elimination of 
artifacts and interference from the computer-aided analysis. 

Problems encountered included some unavoidable interference from 
various electrical appliances around the chamber and occasional loss of signal 
due to a sleeper either rolling on top of the telemetry or knocking off an 
electrode. It has been determined that better than 90 percent of the data 
collected was usable for the subsequent data analysis. 

DATA ANALYSIS 

The analysis of the recorded data involves several processing operations. 
The basic analysis is the automatic scoring of each 30- sec epoch of the 
recorded EEG/EOG data into a sleep stage (or a movement or artifact cate- 
gorization). This is accomplished using a pattern recognition design proced- 
ure. A functional block of the processing and analysis is shown in fig-. 1. 
The analog EEG data are sampled at 68.5 Hz and quantized to 10 bits. The 
restating digital data are then processed by an FFT^ algorithm to extract the 
frequency information from to 34 Hz in 1-Hz increments for each 30 sec. 
These 34 parameters, representing the amplitude squared values ([jlv^/Hz) of 
the frequency constituents in the EEG, provide the input to the pattern 
recognition system for subsequent classification. 



k82 



The design of the classification system Involves a pattern recognition 
learning algorithm? vhich classifies each 30-sec epoch into one of six sleep 
stage categories (stages avake, REM, 1, 2, "5, and k). As illustrated in 
fig. 1, four separate classification systems are designed, using the baseline 
data as the training sample, to perform dichotomous classifications at each 
node (labeled 1 through 4 in fig. 1). A decision tree structure is thus evolved. 
At node 1 the dichotomization involves separating stages 3 and 4 from all 
others. Node 2 separates stage 3 from stage 4. Node 3 provides the identifi-f 
cation of the awake state and node 4 separates stage 2 from stages 1 and REM. 

In addition, the frequency information and the raw digital data are also 
processed in a REM detection and logic operation to detect the presence of 
rapid eye movements, gross body movements, and contaminating noise and 
spurious artifacts. The REM detector uses the total power in the EEG trace, 
the total power in the opposed waves in the EOG and the sharpness of these 
opposed waves to detect rapid eye movement. The body movement and 
artifact detection is based on a double thresholding of the power contained in 
the higher frequencies. If the 30-sec interval contains sufficient energy in the 
high frequencies to exceed the upper threshold, or sufficient energy in the 
ratio of the upper frequencies to the total energy to exceed the lower thresh- 
hold, then an artifact indication is noted. If the energy is concentrated in 
very low frequencies (0 to 1 Hz) and is of large magnitude, then a body move- 
ment indication is provided. 

The corresponding output from this REM detection and logic operation is 
used to supplement or override the classification of the decision tree. A 
movement detection will override all classifications other than stages 3 and 4. 
A REM detection will override the stage 1 classification, and a stage 2 classi- 
fication if that epoch is preceded by a movement; and finally the artifact 
detection will override all decision tree classifications and cause the last 
epoch classification to be carried through until the artifact is over. Fig. 2 is 
an examiple of the computer printout illustrating the operation of the automatic 
scoring system. 

The output from the scoring system is then processed by a computer 
program from which the sleep print is generated. Four adjacent 30-sec 
classification outputs are averaged and a sleep stage noted for that 2-minute 
interval. Each 2-minute interval is plotted to provide a ready display of the 
subject's sleep over the entire sleep period. In addition, the quantities used 
to evaluate the quality of the subject's sleep are also computed. These 
45 parameters include length of time in each stage, total sleep time, total 
awake time, number of movements, number of sleep stage transitions, etc. 
(see fig. 3). 

Finally a statistical summary of each of 43 parameters is computed for 
all of the sleep periods in the cabin for each crewman. These are provided 
in both tabular and graphical form to display trends and inconsistencies in 



kQ3 



sleep behavior. The entire operation, including sleep scoring and statistical 
summary and plotting, takes about 3 to 3 1/2 hours for each 9 to 10 hour sleep 
period using the XDS 930 computer. 

COMPUTER PROCESSING RESULTS 

The scoring of the sleep records is the fundamental step in arriving at 
an assessment of sleep quality. However the output of the scoring systems, a 
stage categorization for each 30- sec epoch of sleep, is still too extensive to be 
easily absorbed. Further data reduction is in order. 

Sleep researchers rely on certain accepted parameters extracted from 
the scored data as well as sleep prints and plots of the delta activity in evaluat- 
ing sleep. For the most part, these parameters deal with the rhythmic nature 
of the sleep and the relative and absolute quantities of the various sleep 
activities. Most parameters are not related to the very fine structure of 
sleep. 

In the course of extracting these parameters, the first ^'•cp is to o'latain 
those which do use fine structure — namely, those dea7.i.xg with movement or 
arousal episodes. Then the 30-sec data are combined to provide 2-minute 
scoring epochs. This tends to minimize chatter in the scoring as the sleeper 
is near the boundary between sleep stages. Such smoothing is provided sub- 
jectively in the hand scoring of sleep records. The sleep prints axe plotted 
directly from these 2-minute data, and they form tiie basis for the great 
majority of the sleep parameters. 

The comiputer provides a listing of the parameters extracted for each 
sleep period. The first k3 items (fig. 5) are the primary output. Histo- 
grams of the duration of various types of sleep episodes (itemi 44, Fig. 3) are 
given, as is a table of the REM-to-REM intervals (item 45, fig. 3). This 
listing is immediately followed by a graphic representation of the sleep stages, 
the sleep print. 

The sleep print of fig. 4 is not taken from one of the crewmen. Rather, 
it is descriptive of EEC changes observable during a typical night. There is 
the regular transition through the stages, reaching stage 4 within an hour. The 
stage 4 episode lasts for perhaps half an hour and leads to the first REM period. 
A second stage 4 episode may or may not occur; but if it did, it would be in the 
second slow wave episode near the 2-hour mark. The plot of the delta activity 
above the sleep print provides a ready reference for slow wave sleep. The 
remainder of the night is spent in a regular REM -stage 2 cycle, with perhaps 
a minor amount of stage 3. Notice the relatively few stage changes. 

Fig. 5 represents perhaps the closest approach, in the nights monitored, 
to the prototype above. There aremany more stage changes than one would 
expect. Indeed this is one of the more striking features of chamber sleep— that 
there are 2 to 4 times as many stage changes as normally encountered. Note 
also the limited amount of slow wave sleep. 

kQk 



With these sleep prints, relative levels of delta activity are also plotted. 
The rigid criteria defined for stages 2, 3, and k provide a coarse quantization 
of what appears to be a somewhat continuous increase and decrease in low 
frequency activity (0. 5 to 2 Hz). To highlight this waxing and waning of delta 
activity, a time history of activity in the delta band is plotted, based also upon 
2-minute epochs. These plots tend to reveal more clearly the rhythmic nature 
of the sleep patterns which may have been obscured by the sleep stage quantifi- 
cations. These also show the rhythmicity of sleep, delta being minimal during 
REM and stage 1 and building up to a maximum in stage 4. 

The sleep parameters are tabulated in a summary chart for each of the 
participating crewmen (figs. 6 and 7). The parameters are subdivided by 
types. First comes the grossest — total bed tim.e, sleep time, and wake time. 
Next is a breakdown by sleep classes and combinations of sleep classes. The 
time to onset of each stage is followed by the average duration of certain 
episodes. Then m.ost of these are converted to percentages. Finally, the 
number of episodes of variouB types and the number of stage changes are 
given. Results for all nights of the sleep study are sho-wn on these charts 
as "well as the avei^ge value for each parameter. 

Probably the most striking item on these charts is the lack of slow wave 
sleep. One creraiian averaged 50 minutes per night for stages 5 and 4 com- 
bined and the other averaged only 5 minutes per night. This result is not out 
of keeping with results of other confinement studies, for example Jay Shurley' s 
analysis of the South Polar Expedition. 

To facilitate the search for trends, bar charts are produced for each of 
the parameters. Fig. 8 shows total waking time. A downward trend is 
exhibited during the first 5 days showing an adaptation to the new environment. 
There is then a rising trend, showing up most dramatically during the last 
5-day recording period as the anticipation of the end of the 90-day run mounted. 

CONCLUSIONS 

Using the biotelemetry system and with a minimum of training of the 
crewmen, it has been demonstrated that consistent and reliable njonitoring of 
the physiology of subjects in confinement can be performed. Liittle crew 
discomfort was noted although some consideration should be given to easing 
the electrode application task. A skull cap or other head covering with pre- 
prepared electrodes (such as that developed by Dr. J. Frost, Baylor University 
for NASA MSC) should be considered for subsequent experiments. 

A methodology has been developed which provides for the rapid process- 
ing of the EEG and related physiologic parameters. The automatic pattern 
recognition sleep scoring system has demonstrated sleep stage classification 
results consistent w^ith those of a human scorer, without the inconsistencies of 
the subjective scoring and eliminating the tedium of manual scoring. A 
statistical summary of sleep parameters is readily computed^ and trends in 
sleep activities are displayed for crew evaluation. 

i^5 



The analyzed data demonstrate a trend toward more sleep in the first 
10 days of confinement and less sleep later on, although total "bed time remains 
about the saxne and both crewmen appear to have obtained adequate sleep. 
This trend is unsupported by crew reports of sleep tinae. 

Total wake time tapered off during the first 10 days reflecting some 
adaptation to the chamiber. The amount of wake time before sleep showed a 
defined increase from the beginning ' -^ the middle to the end of the 90-day run, 
and wake time in bed after sleep also shows a definite increase with time. 
These findings tend to support those of Antarctic groups . 

The sleep behavior of the crewmen monitored during this experiment 
appeared to deviate little during the course of the 90-day run. It was noted 
that both crewmen tended to have little slow wave sleep activity (stages 3 and 
4), averaging 30 minutes per night for one crewman and a miniscule 5 min- 
utes per night for the other. 

The most interesting psychological changes in the creismen occurred between 
days 60 and 70 (see paper no. 29 by J. S. Seenraja and M. T. McLean and paper 
no. 55 "by M. M. Okanes, W. R. Feeney, and J. S. Seeman). It would have been 
impossible to forecast this, and it is unfortunate that the limited scope of 
the sleep monitoring did not include this time period. 

We wish to express our deep appreciation of the outstanding job 
accomplished by the two participating crewmen. With less than 2 hours of 
training, they were able to provide 4 virtually flawless performance in the 
exacting task of electrode application. The success of this experiment 
can be largely attributed to their cooperative attitude throughout. 



EEEEEMCES 



1. Rechtschaffen, Allan; and lales, Anthony, eds.j Ifenual of Standardized 

Teirminology, Techniques and Scoring. System for Bleep Stages of Human Sxib- 
ject^. Publ. 204 (Contract DHEW PH-43-66-59), Hat. Inst. Neurol. Dis. 
51indne s s , I968 . 

2, Oooley, James W. j and Tukey, John ¥. : An Algorithm for the Machine Calcula- 

tion of Complex Fourier Series. Jfeth. Comput,, vol, I9, no. 90, Apr. 19^5, 
pp. 297-501. 

5. Yiglione, S. S.: Applications of Pattern Recognition Technology. 
Chapter IV", Adaptive and Learning Systems , Fu and Mendel (eds.). 
Academic Press, Hew York, 1970. 



k86 



a. 



o 



o .7. 


^ 


o ^ 


00 


^^ 


to 

ll 1 




o 


^ < 


o 


UJ ^ 


a. 


-J o: 




(/) o 




o& 




1- tIJ 


v> 

X 


< a. 


Ui 


o 


u 




lU 
V) 



o 

£0 



CM 




1^ 






i^8T 



COMPUTER PRINTOUT -AUTO/VIATIC SLEEP SCORING 



03::-^: CO 

03:3^:30 

C3 ::?(.: CO 
03: 36; 3? 

^ . .i / i wv.; 
C3:37J30 

C3:.ift*.C0 

C3: 3.^:3.") 

03:3i^:3:; 
03:'»C:C'j 
0i:^C:3c 
03:^1:00 

031^2:00 
C3:^i^l3G 

C3:h3:oc 

03!'t3;3C 
03:^*^:00 
03:'t4:3C 
C3J^£^:0fl 
03:«*b:3c 

C3 5^C:C,0 

C3:^^:^: 
C3:.'<7:oo 

C3S^7:30 

03:'»<^:oc 

03t''*£;3C 

C3J'*5:co 
C3:'»5:3C 
C3:5C;00 
C3J'JC;3o 

03;rji:co 
03;^;i:3o 
03; £2: CO 

C3 5 5c:;30 
C3552:00 
03 5 ^<^: 30 
03! 54; CO 
03:S'»:30 
O35'it;0O 



staoc £ 
r>TAGr r 

STASL i- 
STAv:.r L 

St A -■'».; t 

STAtK ? 

A-^'^K'L 

St AOL • a 

STAof f 

bT'««Jt- r. 

STAGE ? 

STAC-.i; 2 

STAGL L' 

STAOr 2 

A-^'KL 

rvr-' 
Hf '• 

PJTM 

nv 
t?f >'• 

m '.'' 

•^v 
11'' 






AKTlTACT 
Aj^-rirACT 
A;;TirAci 

A^^TIFACI 
Ai;.TlFAC.T 

Af,TirAC.T 
ART! TACT 



2 
2 






STAGL 2 
tTAGL 2 
STA&F: 2 
<:-TAGt ? 
fJ'^AC.r 2 
fJTAOL 2 
ARTIFACT 
A«<Tir ACT 
STAGf. 2 
STAGl 2 
ARTIFACT 
ARTIFACT 
STAGF 2 
STAGf 
STAT.[ 
CTACiF 2 
PT/CL 2 
STACr 2 
STAGE. ? 
ETaGF ?. 
TKAf.filT. 

ART IP ACT 
ATiTlFACT 
ARTIFACT 

ARTIFACT 
/RTlFACt 
Af<TlFACT 
AHTlFACT 
ARTIFACT 
Af^TlFACT 
F&Vt'''fc\T 
v.5VE*'e^ T 



Figure 2 



14-88 



t 

5"*"" 
5 



o 

i' 



to £ 

oc t 

■•■ 333333333333333333333339UUUUUUUUULIUUUU «.«».«.». 

S^zzzzzzzzzzzzzzzzzzzzzzzacKKeKaacaacKKKKK o CO 

^ a. 1 a. LS. X. a. s. X. a. i; XX X.I.X 1. a.1. 1. L X. I. x: o.a.aa.a.a.a.a.n.a.B.«.a.a. 3****^"" <U 

a. 5 ^ 

UJ £ 2 



uu 

I XXItl 



bia>z« •»t-u ZM Z 



»-ll.< J 

o»-«uwi>iw>->wi 

O «»-XZ E£*-la>. 



Z K W WW W J^ U •'• •^ 

111 • US ->e ««>•.•. ■.•.ki-K o •«•• > 

Mm«K«l ZX X".<< •-Utiil>IW^<»-b. • •:'r?**~'*~" 



^ . o»- wkiS»«ii«u»- *u««.5 S>*> 

not OM w<< «« X (owbt> Qu i-^M < w ouwe OM 

WWJ^J JJt-feSj — 



P ♦: .««!-«* JZKJ.r_«.»W«ijJ|{j{^j»»-,5^jSg §2 5 

J < w Suwe OM •• 

... ^ j^^->^>-wSo«o •_ •• 

z** «<»• ^iniainia>e<« wa eoc «««<<•& xin«\x •-•«»•-• •-••-• •-••-x 
- - - - J •-S_t-t-i-»-»-_ *<~«iu».w5— — 



_>M W<< «« X (OWbt> QU l-^M < W aUW« 



Kzx o* hi »-»-t-»- X <<0MZ -Kwb. zaceeen x a.MKwee«< s* 

Zn||llil»-«IMMM •-«»-l: •«lil»-»-t-»-WUO Jtblft. •_ ZW>«<-»->>«»* CO 

>-wbi ux< Z^«aKatacKh.b.h.b. Kexugct- eaczM wzx«>«« •» 

0<20 xK^llt Jl>.k.b.l>. _ _W»- •0<e«(B»XZ «Z ^ZaCU lila» »••••••• _ 

•-1P> Ul >- • M9 ZZZZS b.»-lk. WtomMhK « X* 

o_ at X 111 X ziawK zocuuvjiiieeee • wez iiiwiit>*Mn«arz xwwidWh. w • 

j^f' " »- til ««iii3ii. «<<<« • bibiuiuiz B9oaSaa09sS»-*-»- z z 

<z ^a. ' uiiiwii!iiixw»-»-BO«iitiiiuiiiaBacacx Kiii>K «<«<«<<«x<www5»i>>«»~0 

ZK>- iiiui5eeSeiiie««> kk5E 3333w<^<>'<ikii.»-»-»-»-»-»-»->- xm^o <m 

«u_( oii<v«4«'«<x idiiikieeaeonooSxMX >«ie<nMWMMin«»«iii.%.b.ik.w >- n«* m* 

z •- 3 hi ^« •-•-•-•-•- e »- k. w X X xh.k.Ciik .aSoeSa « 

«l h.^ aMBWMWWMX (•C>e<->»'->illblUhtl|!lllhlWhl»-»-»-»-»-»->-t^^*->*^*- * ^** 

^n« »-*->-aSZaa«9eeazzzz zzzzzzzxzzvatKKKw ^ ••• 

Z _0 J_(_«JJ_> J J^_(^ J «'<<«<hllllUlilUlilhlMhlhlhlklWWWhlhlUWB * ■4*. _ 

****** > •■•%• 

'S'^^i^ o»«Mn,«ia«^«ttoxMM«in«r>w«to>«««n«M«KMa»oa«MQ«M«rk«MoxMf« « • 

■»-»-«o « • •«>«M««rt««.4^.4««MniMMMl)aMntNMnmnnmnAnnn« * «« « ♦ 



489 



UJ 

C9 



CO 

a. 

Hi 

(/> 

o 



UJ 



N ^ 

^ CL 

CM Ui 

^•^ UJ 

»" CO 

«^ CO 

o> 



UJ 

o 




L 

r 



r. 



1: 



I" 

■ 
■•■• 



! I I 



I I \i 



oo 



CO 

O 

UJ 



ro i/^ 



•r-l 



CM 



LlJ 

< < 



CM 



Q. UJ 
O P <^ 

cj g < 
ij-" r^ »— 



cm 

UJ 
UI 

a 



k90 




ii8i 

B 



I 



UJ 

> 
o 

CL 
UJ 
UJ 

(/) 

a 

UJ 
IT 
UJ 



■1-1 



o. 

Q. 
UJ 
UJ 

-J 

CO 



a 



l<-9l 






UJ 



< 

X 

o 

< 



yj 

> 
O 

Q. 
UJ 
UJ 

-J 

Q 
LU 
OS 
UJ 



C0 

< 

Q 

• 

o 



m 



UJ 

< 
< 









n«tn 






OMMO« 

n 
•1 oooa 

m 

I MM« <eM 
I ni 
« « ooni 






« « 

n 

*>« 
m *» 
■>« 
oa*M 
IB ♦•« 






I "•IKS 

• OMOO 
I • ^* 

t 

• M« OM 

• fli<ao 
t tn n 
• 

I infwo« 
t «««4mo 

• N ni 

9 

• St« oo 

f IDO«« 

• n ni 



• • 

• «<«o I 

• • 
I • 

I « «o t 

• v4 n I 

• I 
I • 

• <a u o • 

• m • 

• • 
t • 

• « lu n • 

• « » • 

• i 
I e 
I K> oo t 
t n « • 



o« 4; 



•«r^« o • 



I o • 

I 

I O I ' 



I 

• 

on xo* • 

• 
t 



o • 



«ao 



«a«M« innia« imsm im<*o« ••«» 
naiu «• «MioiM r>»Min«aa> 
n • n n I ( • 

*ooon iiD^oo •••** • om •••«•> 
nn »• onni na'«M>«* 
M • M M • ( « 

• > • • 

in(u«i<joiin««« ••BMiu ••D<e»>s ••^in 

•tn « I nmni • <s cu t <o<r-iani i 
IN I n n • • »<•<•« I 

■••■<eoni>not«* («««■ i9<* <a a^n 
» r^n (u* nin««» «4«4» nvt^t 
in^i**^ • • 

I > e t 1 

iv^oooanao*- iomoimo * iixat 
I Mn x • lomm • •lo • ^n • r< > 
in •4tn«i'«i • 

I • t k • 



a Kt a • « * 



a«* a I 
• •<* a < 
a 

a 



«*« a •> •«•• 



« •HS> » ••■§ 



aofi« a aaaM** 
in rt« a i^a 
a 
> 
t a <•*•« 
> • •> 



•*n« I 
« •«io I 



a o<s*Mo a I 
a funi o a 
an »* a 



a auo« 
a •" 



urn* 
^ *au 

a a a 

•■••ai) a aia««n« a <••* «« aono 



• ai<«« o 
a •««>nr^ 



a O'At « 
a «•«■« B tf) 



a<->n^«<» ant^>« 



a •osiBna) annN 



a m« «<uas a 
a nn o a 



o<e« 
a<^<a 



« atKO 

« • 

I 
.««« I 
r»a« I 
nn I 

I 
««« 
o«n 



n n I 
w>a«o 



)<ts « aa 
r^ ni'« 

n n 



a -inMvian a waaait 



a o-aO'iS'*' 
a v^-^-m -tr 



> M<n«i<«« a as MO • «••<• 



a •■•iu«i|f)<* a ••«•• 



a « aU'O 
a 



a a*<S'Cmo 
• -eixiM 

a 



a «-9 B n a u w-^n a v4^ o 



(•oa o««oia«M a <»<•<»« i 



n< 



o<a4' 



> «-«• «<» a 
a a^iMM o a 
an ••a 
a a 

a <uaa« oo a 
a Aa Aiv« 0% a 
• n a 

a a 

a ««oas« » 
a on o a 
a M •« a 



«nS 
n n 






Aasas« 

w*nnn 

n n 



a'-S 

a 

a ojani 

a «<n 

a 

a 

aoiMM 

• 



o • ««<• o a 



a w4«4 

a 

a o« a 

a ••« • »>. 

• 
a 
a ow«a 

a 



» 
a 

• 



a ««o 
a A 

• 

^•«> a « 

» 

• 
r e«« • oo<« 

• 
• 

a 



>•*•*••»••>••>•••••»•••»•••••••••••••«•• » 


1 1 


• • -- ■ 


SSSfiiJ 


•';?'"-ifj/f"u:ss*'"?; 


• 1 


• • ! 


• 1 


• * ! 




«„«««««««-«—«« » 




.>.M»<>a»* ••••••••••••*•••»•• • 


9 


• * * 


;if5* 


-R— fiJS-RJ-S*'^*: 




* » • 




• • • 


jsss 


oo-oKjg«.gf2*»8; 




» » • 




» • ( 


a xoo 


« —*Mm $ MW« t ««Mwa» • 


a xS 


a M •« • « xfk ( « • 




• • » 




* • • 


a MM* i 


'•5s°SJS:s;tS8'"^*«| 


a « • 




• • • 




* * i 


a « o« 


•S*"S!C*SI6S3S8| 


"* * , 




• ! ! 




• • t 




• ■ • 


»«*« M4V4* 






• * t 


a wn» 1 


-jt*'»ti:s*s:*—''^«s 


»n>««a 




• • • 




• • • 


a ^M* 1 


'tmmio*^ • naaaa t «Mfc«« • 


» •• r> 


r^ «>• vaa • • •• ■ 










a «aM« 


w oa oat • •<«•» • m r^r* ^fi • 


a ^ •■ 1 


»». M»a^* ft » 










a « xw 1 


xatr^oa • a^a a •mmt^rn'm • 


■ fu«n 


1 a M »^. ^ • ^ • • 










• nxo 




a at 


' a oa a ^ 9v • rtM^a • 






















a non 




a ^. au 


t^ war^r^a «-• 










a nr^o 


n xoor^ anooaa«aao« 


a n^n 


^ «4 «« a a ««a • *« tf> • 










a ooo 




a o 


rv M a r«. r>. t «<»• « • 


a v« 








• nM« 




» cM^n 


a aia a to a^ • •••• ■> • 










a ooo 


1 aM««M«i a Mna« a nmmt^'m ■ 


a • w 


l^> <Maa^a «*• 


















a r^no 


1 M M«MM • ana • X'Mfv ax • 


a «n 


^ W • ^ !». • M * • 






a «•{■«• 


1 ••••awo » om^ • ooat^^a • 
1 r> M»af>| •• M* 










|"S*» 


inaa«*M •ar-.n • mo«>«>«« • 


a Ma^^a •• a* 










!S«* 


l-j-nogJongl^aoo^l 










s « o« 


|x2..«.«jaoat««..«gl 


t •'••tl.V* 










»««i>««>«aM* 


la »«*«»«»«»• »i« »>•»«»« •«»«»•»•»« v« k 



CO 






• • • • 

• • • • 

• • • 



• • • • 

• tt • • 
V • • 

to • • 



• •••• ••U ••• 

n«*»« ••£ ••• 

i^m • • • ••»« ••• 

- z.^z •J • ••- M • • 

__• •»•• ifti<iii*^ • • • • 

• • •-&. « ooo • oSSS»- • w ••^S 

: i:SA SSjb SǤ i5iif. ni^ ^rf^ 



• » snAi 

• »- • 

• 'WW 



>r ii: 



|i« nil iiiil 8§l S|^ 

M I»-~ xan* • ixmS l».«P ta.lk.la.lk. ♦-»-»-»-►» h.»- 

9 •• >■ • WM<« w5ik <<<«<• ^az lauu 

: ih ma ll» *!: nn sisis lit m 
S "• 555*! **!5 "= s»s «!«? SK »» 

I |l£ £E£H llff III »» mil £££ s&s 



• • • • w3 a • • • 
« • * • htS waw • 

• • • • • • J OMW • ' 

• « • • • oa^ 9 99 * ' 

• « a • • • a aaa •* 

• • • • • a^ ••••«< 

uuuw • u Bj^i^B* 

faiuiitu • u«Q SSas 

ml |i! »»« 



492 



UJ 



o 

Ql 

UJ 



> UJ 

tr K 

S *^ 

=> ^. 

>- 

< 

9< 

^ < 



UJ 



!«»«• (M inn; 



n* 
■>■> 

M«BM 
»* 

om>a 
in« 



r> nim 

♦ ♦ ■ 

nm 

* « 



ID « 

•oats 

tnin 

« « * 
mm 

« « 

•0 «« 

ion 

<e ni« 
* * o 



o«* 
o<em 

« PI 



<« «* OM 
M* M 



« (O* OM 
« «MO* 









« lu « u « 
nim fu 

C0(SOO« 



MID * 0« 



<u «> o o n 

ri »* 

« « ooo 



* BOOM 

•0 o <o 

cu 



o« « uo 
n o>« « 

OI*<UO«I 

moi o 

OI wt 

oaoon 



n 



■IIU 



* 

nia 

in 

o* 



« cu ^ 
nu 



m« on 

ncu (C 
n (u 



ni <u 



» IV 
<u •^ 

Miu on 
v\ o 
cu cu 

«4> IU4) 

m cu 

m cu 



n ♦ 
m nt 

■«« OIM 

* •<• 
PI p> 



«Min » m •• 



« «> o • * <o 

«i4 «-• I V^l^ • I 



« ■) O • HI lU 



• • • • 

•lunt • r>nip> • ninn • oivmox ••«< 
I n w • o»tMPiPii««« «i(r> 

• It • 

• f • • 



« t MX < 



• nioin o • <a«(u 
<onia« I 9) 



• * MP) o • *mo 



m oo • «« 
ni • niK) • 



o «> o I cu cu 

•4 > cu* • 



O I < 



4> I 

* I 

V4 • 



110 *u>n 

•o •<« 



tfipirv 



• inio (u^a I ^(Uoi 

f» p»t» • »»"-• 

** I 

I 

'•niwpxu • piiu<o 

«iu«> • <n 



« oo to n ■ 

cu • v4 ■ ■ (U 9 



«4rv (uu a «^ao 
«4 a 
a 
4«-t«iv« a cn4>m 
« lueo a en 



KOOao*-* • <o*'^ 
IV (um a ir. 



«c (u cu ^ 
* ui *o 



o ao a ocu o a wr 



a «) cuc*> 
a Q\ 



•0 * a ' 

• • * a 

I CU a 

I a 

oo lO a I 

I a a CU a 



O O* a 

cu nin a 



o* o 
n xcu 
cu <u 


cu a 
1 a 

a 


ao cu« 
in cu 
cu cu 


1 * <a* I 
1 cu a 
1 a 



ao«o O a 
P)« a <o a 

cu a 



cu cu «o a 
•«m • « a 



ocu * a 
*«* • « a 



IV P) -•« 


iri •«in o 
cu 

(U 


in en in w 


• a M o 
in cuo 



a pirv-* 
a cuiv 



a ooo 

a MOi 



•a m>» t 
•<iu a 



cu a 
I o • 

*4 a 



•^cuptm 



mmo 

lUlv 



o> •to 
Airv 



HI « 



o oo 
o 



o oo 

lom 



<U lUiO 
w4 «-l^ 



O «>lOIO 
<4<o lU 



OMO O O « 
« lU 



I ^ v^ocn 



4> <M*> OP> 



in IT v^otn 
« cu 



lU »»«OP» 

IV cu 



•4 ao * orv 



-»■ O C\. O IT 
•HI* -< 



* O^ O O ao 

«u m •< 



cu tf) *-«ocu 
p) « 



o «ic>o<n 
«4 ^ «-• 



(n «-av40 O 

4> n 



m * oocu 
cu >o •< 



ID'^O • *IUiO«>fU 



HI MID a ••<««> •• 
rv « I lox « 



*oin • ino«<as< 
rv <o I mva (u 



«OOI4l<Bm*« 

^ IV i « cu 



«4«-tau r«««an« 
•0 IV a pi«4 m 



IV PI (u a mmin *-o 
rv pi. a cu cu 



io<-<o a aao«inao 
iv ^ a en •t cu 



I orv a r^Ts.m*ai 
«o a * cu 



m * cu a ^io*m^ 
00 flo a cu 



ivp>cn 
ou rv 



m lucu 

IV IV 



a oaa«i 
a cu 



«o ocu 



cu om 
ao m 



00 •-••o 



ao fv 



•0 o* 
ao <e 



•<OP) 
ao IV 



*4Cn cu •ten 



I '•ID 

en 



leu* 
at 



IIDW 

cu 9 



0) 

bfl 






• • r 






• zn 



z • « 



»-a. • 
m uo. 

OC lilbl 

•-• -tu 
i& en J 



ii^»« ••«•»« 



^ • Ullal 

zx5o 

lallal ^ < 
^ •"ft.. ii'^JSltt • !.«»-»- 

• _ti(!a< aeeo • M*nw 



• • • • en * * 

• • • • »-«n • 

• • • • X -It 'J • •»- 

• ••• iBKtaf*^ »• 

niin«« zenof«> ••o 

• W3>>K ••ui 

utuw • >ezzu • •m 

I90e • OlEeiai*- •Id 

«««Z Z<ZIEZ U1EI>. 

►-►-»- 111 •- E ••«> 

enininiE iLia.i>.u. ••»- 

eeeez »- bi 
»-»-»-»- u ox 

lOwiAM mnac Otoi>« 

lEKeEac eeee « taiai^ 



• •u 



U. 0C»- b.la.1 



ft » . . . »-»-•- 



-. _ <«< < • IkOZ 

O* litWWU OcacKKE CI w 

macacK 3333ii> a.x 

eceo ooooac biuw 

ift.la.lk.la. ]CW> 



wwuu UU.UWU <^n 
wwwM otaeacacae •.• • 

CCCX lallallilMlal •-•-•- 



<«««t« 



»- a. 
enwa. 

OC UUi 



b.«)-i a.aa.e. 

in ul talUIUI 

UIO liJ lAlbllal 

Kzar jj-t-t 

n—ut incnmena. 
IkOCt- w 

U^b, l>.b.lLh.W 

aio< o«>a>e.j 
en 

lilldlal •«»>»* 

«<< UlallalWe 

X 22 eooa 






• men uinn • • 

• -t ObllU • • 

• «ih. eoo • * 



u wtt.a.oz 

u*o lallliai < 

-» z »- wx 

ino< Z^CatU 

z ia<wa. 

ta.'cn cwecsatki 

«> « laO • <9 

!»•• " 



>ZE 4 

e*la<»- 



?&rs 






493 



sssssssssssssss 


KHMMMKKWKHKKKMKKMKK 
MKMWKMKKMXKKMKXMMHM 








1 



LU 



z 
< 



xxxxxxxxxxx 

>X>rM>rxXXXXXX 
XXXXXXXXXXXXIP 

xxxxxxxxxxxx-^ 



xxxxxxxxxxxxxxxxxxxxxxxx 
xxxxxxxxxxxxxxxxxxxxxxxx-^ 
xxxxxxxxxxxxxxxxxxxxxxxx # 
xxxxxxxxxxxxxxxxxxxxxxxx 

■ 
xxxxxxxxx 

XXXXXXXXXPt 

XXXXXX>XX 9 



XXXMXXXXXXXXXXXXXXXXXXXXMJ^ 

xxxxxxxxxxxxxxxxxxxxxxxxxx 
xxxxxxxxxxxxxxxxxxxxxxxxxx 
xxxxxxxxxxxxxxxxxxxxxxxxxx 



X X 

X X 
X X 

X X 



XXX 

X X > I 

XXX 

XXX 



O 1 



X X X X 

X X X X 

X X X > 

X X X X 

XXX 
X > w 
XXX 
XXX 



XXX 

XXX 
XXX 
XXX 

• 

XXX 

XXXI 
X X > 
XXX 

• 

XXX 

X K X : 

XXX 

XXX 



00 



Ul 



xxxxxxxxxxx 
xxxxxxxxxxx: 
xxxxxxxxxxx: 
xxxxxxxxxxx: 



X X X X X X 

K X X X X X • 

X X X X X X 

X X X X X X 

• 
xxxxxxxxxx 

KXXKXKKKKKfn 
XXXXXXMKXK 



XXKXXXMXXKXX 

XXXKXKXKXXXXtM 

KXXKHKXKXKKX 



m 



X X X X X X 
K X X X X X 



xxxxxxxxxx 

XKHXKKKKKMM 






u 



f 



I 
o 






k9h 



MEDICAL EROGRAM 

By J. R. Wamsley, M.D.^ and B. J. l^ers 
McDonnell Do-uglas Astronautics Company 



SWSMHI 



Medical procedures were planned to provide maximum data on crew medical 
status throiighout the test within the constraints of limited pass-outs and 
onboard crew capabilities. These procedures and associated studies ty outside 
investigators were accomplished without significant problems. Evaluation of 
the results confirm that the SSS environment was benign medically. 



IHTRODUCTIOH 

The 90-day manned test medical program was devised primarily to provide 
near-real-time medical-status infonnation for the crew. Secondary goals 
involved evaluations of specific stresses encountered during the test, e.g., 
confinement, altered day-night cycles, low- level CO2 exposure. Laboratory pro- 
cedures were constrained by limitations on sample pass-out and by crew capa- 
bilities for onboard tests. During the test, the medical director maintained 
daily records of medical procedure results, which allowed, on several occasions, 
improvisation of additional tests and, once, directions for medical treatment 
of a potentially dangerous bacterial finding. Medical operations were gratify- 
ingly smooth with contract physicians on duty for the duration of the test. No 
medical emergencies were encountered. 

MEDICAL PROCEDURES 



The medical procedures planned for the operational 90-day manned test of 
a regenerative life support system were as follows: 

Blood biochemistry 

Venous electrolytes (m, K, CA, CL, HCO5, VO^) 

Venous Pqq , pH, erythrocyte electrolytes (SMRL) 

Uric acid, bilirubin, total protein, A/G, SGOT 

Lipids (3MRI) 

Serology (LRC) 

Vitamin D assay (^te,ssachusetts General Hospital and Holmq.uest, MSC) 

Hematology 

CBC, differential 
Hematocrit 

495 



Body fluids and lean body mass 
Total body water (tritiTom) 
Plasma voliime (RISA) 
Skin folds 

General medical status checks (daily) 
Private medical interview 

Vital signs (temperature, pulse, blood pressure) 
Body weight 
EKG weekly 

Exercise program o 

Pretest and posttest evaluation (Balke/Astrand-Rhyming) 

Daily ergometer/Cardiotach. evaluation 

Weekly ergometer 02?ygen consumption (Webb, MEM) 

Pulmonary studies (LRC) 

Forced vital capacity flow volume loop (weekly) 
Alveolar air samples pretest, midrtm and posttest 
Sleep respiratory rates 

Blind spot mapping (NASA Ames) 

Urinalysis 

Toxicology sample 

Routine urinalysis 

Total urine output 

Urine electrolytes and acidity weekly (biweekly last 50 days) 

Microbiology program 

Potable water onboard monitoring 

Wash water onboard monitoring 

Cabin air and surfaces sampling 

Nasal and pharyngeal samples 

Pharyngeal wash (viral) 

Skin sites 

Potable water microbial monitor (Wilkins, IBC) 

There were several changes before test start largely because of a change in 
medical direction after the 5-day run and partially as a result of Operational 
Readiness Inspection Committee (ORIC) considerations. The late addition of 
urine chemistry prevented acquisition of pretest baseline, complicating post- 
test analysis of the data. These chemistries were primarily directed at 
studying CO2 exposure effects and had little impact on evaluations of crew 

health and safety. Several of the procedures will be reported elsewhere by the 
princ ipal inve st igat or s . 



496 



RESULTS 



Basal Biomedical Data 

Basal oral temperatiire , body weighty "blood pressure, and pulse rate were 
obtained daily as soon as possible after awakening and before breakfast. Crew- 
men (cm) accomplished the procedures onboard and reported the results to the 
medical monitor for recording (except oral temperature which was displayed at 
the medical console in the control room) . There were no significant trends in 
either p'ulse rate or blood pressure. Oral temperature in crewmen 3 and k- 
illustrates their adjustment to a reversed day-night cycle (fig. l(a)). It 
would appear that this adjustment was not complete in respect to oral tempera- 
tvire for at least 2 weeks ;, perhaps longer. Body weight changes are illustrated 
in figiire l(b) and are adjusted for individual uniform weights. Short-term 
fluctuations probably represent alterations in state of body hydration. Taking 
these fluctuations into accotuit it is likely that the only significant weight 
changes occurred in crewmen 2 and k. Further changes occurred in the 21 days 
posttest resulting in a net gain in crewman 2 of 4.75 Ih and a net loss in 
crewman k of 1.25 Ih. In spite of these final changes, the net for the crew 
remained +2.25 Ih. This probably represents a real weight gain in crewman 2 
and a net loss in the remaining crew members. These weight changes are reflected 
in skin-fold thickness trends (fig. 2). Weekly electrocardiography revealed no 
significant trends . An arrhythmia was discovered in crewman 2 which was without 
medical significance but had been undetected before the test. Questioning 
revealed that crewman 2 had noticed this rhythm variant at least a year before. 

Exercise Program 

The crew exercise program was directed primarily at evalimtion of bicycle 
ergometry in maintaining cardiovascular fitness. Exercise, however, was not 
restricted to ergometry and crewmen pursued personal programs of varying inten- 
sity. The basic regime consisted of daily (5 days/week) ergometer exercise at 
a predetermined submaximal workload. Resting heart rates for 5 minutes before 
exercise, during 15 minutes of exercise, and for 10 minutes of recovery were 
recorded. The workloads were originally established to produce peak heart 
rate responses of 150 to l6o beats per minute. These preset workloads were 
adequate for crewmen 1 and 4; inadeqijate to prevent excessive pedal speeds in 
crewman 3. The workload for crewman 3 was, therefore, increased. Crewman 2 
devised his own program; for 30 days he relied on ergometry alone, for the next 
30 days he increased his ergometer workload and performed an increasingly stren- 
uous extra exercise program, and during the last 30 days he continued at the 
final ergometer workload with minimal additional exercise. Extra exercise by 
crewmen 1, 3^ and h varied from minimal for crewman 1 to strenuous and steady 
for crewman h, strenuous and less steady for crewman 3« Cardiovascxilar fitness 
was evaluated pretest and posttest by means of the Balke Optimal Work Capacity 
Test (table l). Figure 3(a) illustrates heart rate responses to ergometry 
during the run. The curves for Individuals are inconclusive, but the group 
mean x suggests a de conditioning trend. When the responses are corrected for 



k^-'7 



changing -workload (h/w = Heart rate/Workload) , however, an overall improvement 
is siJggested. This improvement is supported by the trends toward increased 
oxygen consumption (fig. 30^)) and "by the posttest Balke scores. The latter 
demonstrates slight de conditioning in crewman 1, improvement in crewaen 2 and h 
and no change in crewman 5- In view of the extra exercise programs, it is con- 
cluded that const ant -level legs - only exercise is probably insufficient for 
maintenance of cardiovascular fitness, as measured here, during prolonged 
confinement . 



Clinical Biochemistry and Hematology 

A clinical blood biochemistry battery (SMA-12) and a complete hematologic 
evaluation were performed biweekly. Figures 4 to 9 illustrate selected param- 
eters from these tests. 

Figure k illustrates blood urea nitrogen (BUIT) and alkaline phosphatase. 
Each individual serves as his own control with limits determined by the pretest 
mean ± "t" standard deviations; the "t" value based on the n-umber of pretest 
samples. There were no significant changes in serum alkaline phosphatase. All 
BUlf's are within laboratory limits of normal, but significant elevations are 
seen in crewmen 3 and k in respect to their own control limits. The elevations 
in crewman 5 are fairly constant and are still being evaluated; the elevations 
in crewman k are less constant. It should be noted, however, that the time of 
sampling in crewmen 5 and k- is late afternoon in their day-night cycle as 
opposed to a fasting morning sample pretest and in crewmen 1 and 2. This vari- 
able makes evaluation of chemical changes most difficult. It is concluded that 
the BIM changes are probably of no clinical significance. 

Sertim albumin and albumin-globiilin (A-G) ratios are illiistrated in fig- 
ure 5« All crewmen show a depression in A-G ratio on day 59 • The outside 
control cre-wman showed the same drop, however, and the "change" is without 
significance. 

Serum glutamic oxalacetic transaminase (SGOT) and lactic dehydrogenase 
(IDH) are illustrated in figiire 6. Crewmen 2, 3^ and k demonstrate significant 
changes. The initial elevations in crewman 2 are not only statistically sig- 
nificant but also reach values ordinarily considered pathologic and were con- 
firmed by another laboratory. These enzymes are used as indicators of cellular 
damage but we have no other evidence for such damage. Crewman 2 had experi- 
enced considerable work stress during the first week of the test and we are 
hypothesizing a relationship with that stress, coupled with physical fatigue. 

Serum calcium and inorganic phosphorijs trends are illiistrated in figure "J. 
Complete analysis of these data are incomplete, but they suggest significant 
changes in calcium-phosphorus metabolism. The trend suggests an initial depres- 
sion in seiTjm calcium, followed by a rise to a peak on day 39 and a subseq[uent 
downward trend. Serim phosphorus reflects the calcitm changes. A relationship 
to CO2 expostire is possible and is being investigated by further analysis. 



i^98 



Hematological changes (fig. 8) in cre-wmen 1 and 2 are unremarkalDle . Crew~ 
man 3^ however, demonstrated a disconcerting drop in erythrocytes, hematocrit, 
and hemoglohin on day 25 followed by consistently low values for him. Crew- 
man k shows some of these changes also. Again, these may be related to diurnal 
variation or to the preceding exercise. Haptoglobins in these crewmen do not 
clearly siJggest a hemolytic cause. Hie combination of low hematocrit, elevated 
BIM, and mild stomach symptoms in crewman 5 siJggested the possibility of gastro- 
intestinal bleeding. He also reports a family history of peptic ulcer and a 
previous concern for the possibility of that disease in himself. A stool speci- 
men obtained on day 32 was negative for blood, but the specimen was small. At 
this writing we are continuing our evaluation but the whole syndrome may only 
represent a diiimal phenomenon. 

Urine Chemistry 

Twenty-four hour urine collections were made weekly tmtil day 53^ then 
biweekly. A 10 percent aliquot of each voiding was collected and frozen for 
pass-out. Part of the sample was separated after pass-out and saved for toxi- 
cological contingencies. The remainder was subjected to routine urinalysis 
and biochemical analysis for sodium, potassium, chloride, calciimi, inorganic' 
phosphorus, total titratable acidity, ammonia, and pH. Titratable acidity and 
pH reveal no discernible trends as neither do calci-um, phosphorus or Ca-P ratios 
(figs. 9{a) and (b)). All these data, however, will be subjected to analysis 
of variance for possible relevance to CO2 exposure. There is none apparent in 

these figures or in scatter plots developed during the test. Figiire 9(c) illus- 
trates sodi-um/potassium excretion ratios. Na/K is related to aldosterone pro- 
duction and changes may be related both to diurnal cycle changes and to stress. 
¥e are evaluating these relationships, but have only preliminary impressions at 
this ivriting. Sodium excretion relative to potassium appears to be consistently 
lower in crewmen 3 and k- for nearly the first two thirds of the test. This 
depression of the mean for the two crewmen is primarily a reflection of the Na/K 
in crewman 3 who may have recycled biochemically much more slowly than was 
apparent subjectively or in his basal signs. A peak is clear in all crew mem- 
bers at day 7^- !niis point in the test follows a period of subjective crew 
stress which reached its cuMination in a "sensitivity session" on day 69. 
Sodi-um/potassium ratio as an indicator of stress as well as an indicator of 
aldosterone production, per se, is still -under study. 

CONCLUDING KEMAEKS 



Medical procedures described here, as supplemented by other investigations 
reported elsewhere, were quite adequate for monitoring crew health and safety. 
The changes observed are interesting and under further analysis but seem to be 
irrelevant to the overall test conditions, that is, the SSS environment was 
medically benign. Because of the essentially benign environment, it appears 
that 90 days is probably too short a period for complete evaluation of reac- 
tions to intermittent stress or to low- level environmental variables, for 



^99 



example, low-level CO2 exposure. Some of the data are suggestive of basic 

■biochemical responses, as for example, apparent calcium-phosphorus metaholism 
changes and deserve further study. Tiie use of urinary Na/K appears to offer 
potential as a simple stress indicator and also deseiTves further evaluation. 



500 



to 
I— 

< 

CO 



CO 



i- 


< 


o 


Oi 


< 

< 


< 


o 




i^ 


:^ 


ai 


Q 


o 


1— 



O 

UJ 

I 

< 
CO 



< 









UJ 



< 

UJ 

a: 





Cul 


















BALKE 

INDEX 

(%0F 

AVERAG 


>— 1 


ITk 

en 

»— • 


1— 1 


J5 


OO 


^ 


OO 


^ 




1— 








































o 




















yj ^_^ 




















^ E 


















UJ 


>^ CD 


















t/J 


$^ ^ 


















■i^ 


O — 


















O 

UJ 




CO 

o 


CM 


OO 

• 

OO 


o 

• 
NO 


• 
NO 


• 
NO 


C3 

in 


On 
NO 


X 

UJ 


O E 


CM 


CM 


1— 1 


■— < 


■— « 


r-4 


t—t 


1— i 


fe 




















UJ 


^ ^ 


















1— 




















ID 


^ 


















Z 


o 


















S 


^ 


















1 




















< 






















^ c 


















lZ 


§1 




















SI 


OO 


OQ 


C3 


^ 


^ 


CM 
UTk 


o8 


§ 




_l 1 


^O 


OO 


t— 1 


o^ 


CM 


CM 


OO 




^ E 


1— t 


t—t 


r—* 




»-t 


1— • 




l-H 






















_j 


















2 _j 


















OSc 


















UJ Q •— 


CM 


U\ 


£5 


^— 


OO 


OO 


NO 


OO 


sss 


CVJ 


CM 


CM 


1— 1 


«— * 


■—4 


1—* 


»— f 


















»- Qi 


















1— 


















1— 


















S g. 




lA 

9 








it 


CM 


o^ 

9 


r-: ^^ 


1— 1 


s 


OO 


OC7 


cK 


•^ 


oJ 


•—I 


^ ^ 


OO 


ITS 


m 


r^ 


t^ 


lA 


NO 
























A 




A 




A 




A 




A 




A 


"^ 


A 




A 


^^ 


UJ 




ZD 


:z 


ZD 


Z 


=3 




=3 




;^ 


OC 


ZD 


oc 


=3 


Ql 


=> 


oe: 


qe: 


►i. 


1 


1 

1— 


1 


1 


1 


1 

1— 




UJ 


CO 


UJ 


t/i 


UJ 


CO 


UJ 


CO 




o^ 


o 


Ql 


o 


0^ 


o 


C^ 


O 




a. 


Q- 


Q. 


Q- 


a. 


a. 


a. 


Q. 


2: 


















< 


















1 






















'^r 




1— 1 




pr> 




CM 


t ■ 1 


















Ql 




















o 



















501 



I 



1 



I 



I 



i 



I 



I 



f 






iJ. 







t I 



z 



5 



I 



J-L 



I 
I 

£ 



£ 



I 



I 



r 



£ 



r 



£ 



I I H I 



VL 



m 
cs 



<o 



in 
in 



in 



in 



in 
ft 



in 

(M 






W fO 



Sin 



S !S SS £ 

€•9 **• c^ cn 



60 r^ CD Ifl 
fO fj W CJ 



00 ^ CO m 

CO C* ffp fj 

a 

IX 






0) 



u 

a 

a 

-M 

o 



o 

•r-l 



X2 



<y 
•i-i 



502 



OQ 







m cK S ITi f^ l«^ 
■"• I— « I— f i— I I— « I— I 



8 



^ 



s 



in 



R 






-s 



lA 








in 






• 


S^ 




• 


4i^ 






S 


I3 


in 


>r 


.1-1 
Qi 


1— 1 

o 


-«* 


< 


^ 


o 




o 


o 


§ 


U 

^ 


o 


• 


i$^ 




3 





-^ 



m 

CM 



-S, 



in 



__ C3 
•—I 



— in 



— 'C3 



P^ 



<M 



cn 



503 



(WW)S 



« 



(WW)S 



o 

• 



us 



O 






1 


1 


/ 


—1 — 




lA 




r>- 




vd ~ 


^^ 


+ 


\ 


CM „ 




i-i: 


k 


z o 


\ 


< u3 


1 


1 ^ - 


u. 


St; 




^^^ o ^ - 


r 


""""l 



N. 






>ik 


OQ 




7 


_J 




/ 


m 




1 


CM 


^" 


1 


•■ 




I 


o 




1 






I '^ 


II 


— 


\ o- 


< 




) 




— 


/ ^ 


o 




^' 


z 


— 


-< , 




— 




s 



g 



s 



-8 



/ 




1 


^ 


1 


CO 


J 


-A — 


^^r 


o 


j^ 


• 


^^ 


I-H 


1 *^ 


U 


J o 


< 


i^'^ 2r 


H- 


^.^*^^^^ 


x; 


^^^ Z! 


o 


^^^^^ ^C 




> 1 


UJ 


^^ UJ 


I— — 


a: 


LU 


.^^^P^ 


M>^ 



^ 






C3 




<D 


CD 


^ 


1—1 


-M 




TS 


>- 


-3 


O < 


o 


G 


8&5 

LU 


•I-l 


1— 


1 


S 


c>i 




<a 


o 


^ 


r^ 


bjo 




•r-l 


s 


fl4 


^ 





CD 



(WW)S 






\r\ Q \r\ 

r>- r«- vo 

(WW)S 



^o 



^ok 




8 



to 



- S 



its 




• 


>o 




m 


s 




o 

05 


m 


^ 




ITS 


o 


cu 




B 


•i-i 


S>- 


^ 




< 


S 


^ 


o 


V 


ir\ . 


a> 


Q) 


40 4 
TEST 




U 

^-> 

a 

o 




u 


ho 


^ 


u 




^ 


xi 


I— < 
o 


a 


ft 




S 


■3- 


CO 


ir\ 




bD 



m 



i^ ^SS^ggs gs 



<M 



cn 



^o o- oo 
^ M/H 

s s ^ 

r-H 1-4 I— f 

XMByO 



fe 



505 





\ 




) 






/ 




























\ 




\ 




\ 




\ 
















/ 


< 


/ 


^ 

^ 


/ 




1 





\ 




\ 
























J 






/ 




\ 


r-i 


\ 




A 


i 


\ 
















1 


CO 

< 




CM 


/ 




1 





/ 








/ 
























1 






1 






1 






; \ 






\ 






\ 






/ 






A 








) 






f 


»-*. 


* 




CO 

< 


/ 




5^ 


/ 






1 







\ 




\ 




I 




\ 








1 




/ 




/ 




< 








/ 




( 




\ 




/ 




\ 


CO 


) 


m 


/ 


1— t 


1 



o 



oo 



o 
oo 



ITS 



in 



s 






< 
in ^ 



§ 



crv 



S 



CM 



18 



m 



•i-i 

DO 
U 

i I 

O ;3 



s 

a 
o 
o 

c 






CO 






ir\ 



pr» CM f— • prj CVJ »—' 



(f\ CM 



cr\ CM 



CM 



CTk 



o 



506 



< 

i 

EC 
O 






1 



■:VX 



^ 






O O O ^ O O ^ 1 
9 (*) CM <- « en CM < 

{% »u«) Nna m/BW) sOHd Ml V 



m 

a 
to 

o 

43 
a. 

(U 
C! 

•r-< 

•a 

"^ 

d 
a 

o 
u 



d 



o 
o 

1—1 

CQ 
i 

0) 



fe 



ri «M »- 

(KBui)Nna 



» CO «*i •- 

(|iu/nui) SOHd JIIV 



507 







ci 
u 

I— I 

o 

u 

I 

•p-l 

a 
13 



i 



i-H 

a 

03 
i 

in 

a> 
u 

S) 

P4 



M 



s/v (% I/V9) NiMineiv 



D/V 



(% lAiQ) NiiAinaiv 



508 



=^ 
















m 



^ 



i 



I 



o. 



s 

.UJ. 

u 



so 




i 



mh VWW 



1 



w 



M*** 



iii 







:•:•: 



I 




ftW* 







r 






I 






i 






1^ 



109S 



HQl 



loss 



HOI 



+ 







W 



f 


1— 1 




T3 


+ 


s 


10 


rt 


¥ 


H 


1- 


O 


7 


O 


u^ 


M 


GC UJ 


«\ 


all- 


CQ 




0) 




a 


in 




e> 


d 


"P 


0) 


e> 


a 


T 


:3 


a> 


u 


aa 
«7 


^ 


es 


1 


as 


• 

CD 


,_ 


(U 






r» 


be 


p« 


•!-< 
fe 


«»» 




M 




<& 




1^1^ 




K UJ 





509 




CO 
;3 

O 
4:! 
Qh 
0} 

o 
Si 
a 



o 



:3 
•1-1 
o 

s 

CO 






fe 



e s» un « rt 

(%Biu) ++B3 (%Bui) d 



(%8uj) ++B3 



(%Bui)d 



510 




i 



^ I 



iS 



! 



few 






<-^^ 

S 



^H 



■ 



IB 



I 



^ 



T" OT 



I i 




!■ 



«i 



J* 




1 




s 






+ 






en 






w 






+ 




• 


10 




t>> 


9 




^ 


^ 




a 


+ 


• 


a 


uit to 


TJ 


£s; 


S 


IB 




i-H 


^ 




rt 


o 




<1> 

a 


1^ 
a 


09 


O 


w 



D in «r le u» « »oesie«' in a y* 
gpixaeu (XUiB)a9H {%)13H {OIXOSM (%)S.91S 



eS 



00 

0) 



fe 



511 




•7 






m 






CM 






+ 






^ 


• 


• 


+ 


73 


1 


OC UJ 


cts 


i-H 


a. h- 




o 




CO 


c 




c 


o 




cu 


u 


m 


a 


1 


o> 




00 


eo 




01 




^.— ^ 


be 



ft 



UJ C/9 

QC UJ 



Pn 



(%) S.93S 



512 




o 



oo 






oo 






'd- 






oo 






I— 1 






oo 






r>- 






1 — 






■^ 




CO 


1^ 




u 

0) 


o 




-M 


r^ 










o 

•l-l 
■+-> 


cr\ 




0) 


NO 


>- 


fn 




< 


O 




Q 


X 


NO 


1— 

to 

1 — 




ITS 




•r-t 
U 


cr\ 




P 


LTv 






vO 




• 

05 


^ 




<u 






•I-l 


c^a 






CO 






ITN 






CM 







oo 



(^H VE/baiu) AiiaiDV 3iaViVdili ^ Hd 



513 




oo 
oo 



oo 



oo 



I — 



r>- 






vO 




• 




>- 




CO 


< 


i 


^0 


Q 


d 
•i-» 


s 


1— 

to 

IxJ 
1— 


1 


NO 




1 


LfN 






cr\ 






ITS 




•r-l 


^ 




fXH 


o 






rr\ 






CM 






cr\ 






LTk 






evj 







OO 



8 8 8 

CTk CM »— • 



^ LTk C5 Lf\ ^ 

CM ■— • •— • 



wnioivo oiNvoyoNi 



5lii- 



n3 




CD 



oo 



o 
oo 



"^ 



o 






h"-. 






s 






s 






LP* 






lA 




• 


CD 


>- 






< 


■— ! 




o 


O 


in 




H 


"«;a- 


1— 


o 




00 


U 




LU 




o 


1— 


' 


■«;t 






in 




U 


<r\ 




f3 


CD 






cr» 







K^ 



CD 
CM 



in 



in 



^ NO 



CM so ^ CM NO ^ 

^ IX 



CM 



515 



MECROBIOLOGY RESULTS - DiERMAIi AMD ENVIROlMEINTiy:. SAMPKENG 

;^ K. J. Levlnson 
McDonnell Douglas Astronautics Company 



SUMMARY 



The 90-Day SSS test offered unique opportunities for obtaining long-term 
microbiological data in an isolated environment. An illustration of the sam- 
pling protocol utilized for the microbiology program is presented. Skin sites 
■were swabbed -weekly to determine potential shifts in normal microflora. Wo 
significant quantitative alterations were found and there vere no observable 
shifts in predominant isolates. Reyoier air samples and surface swab samples 
were used to obtain microbial counts and identification of predominant types. 
The predominant organisms in both of these types of environmental samples 
remained those carried by the crew members. An increase in ntjmber of types but 
not in number of viable particles in atmospheric samples coincided with cata- 
lytic burner shutdown and juay be coincidental and tmrelated to that occTirrence. 
Post-test sampling of hardware and surfaces was accomplished but results are 
not yet available. 



INTRODUCTION 



There were four unique characteristics of the 90-Day SSS test which 
enhanced the microbiological data obtained from the ejqperiment . A truly micro- 
biologically closed system was maintained by operating the autoclave in the 
pass-through port for 50 minutes after each weekly passout. There was no pre- 
test quarantine period for the crew, so that any potential exchange of micro- 
flora could be followed from the outset of the test. Also, this provided the 
opportunity for the inclusion of "off-the-street" microorganisms into the ecol- 
ogy of the simulator. Another lorportant feature was the rapid processing of 
samples with a maxlm-um lag period of 1 hour between collection and primary 
incubation for nasophaiyngeal cultTires and I.5 hours for the deimal anaerobic 
plates . 



MATERIALS AND METHODS 



Figure 1 illustrates the sampling protocol utilized for the microbiology 
lirogram. Nasopharyngeal imterials, methods, and results are discussed in paper 
no. 35 of this compilation. 

Three dermal sites were chosen for study, the axilla, perineum, and the 
first interdigita,l space of the right foot. The crewmen were trained prior to 
the test in sterile technique and proper sampling procedures. Consistency in 
technique was stressed. Saline-moistened cotton-tipped swabs were used to 

517 



obtain, specimens immediately prior to the passout each week of the test. Spec- 
imens were swabhed to hlood Eigar and differential and selective media for aero- 
bic and anaerobic bacteria and fungi. After appropriate prionary incubation, 
the isolates were described, assigned numbers, strealsed for purification, and 
transferred to Trypticase Soy Agar (TSA) slants for shipment to Langley Research 
Center (LRC) for identification. 

Contaminated Millipore water monitors incubated in the on-board laboratory 
were passed out of the simiilator, growth streaked for isolation, and transferred 
to slants for identification. 

Reynier air samplers were operated every^ 2 weeks for 1 hour in the forward 
(equipment) area and the aft (crew) compartment at a flow rate of 1 ft^ /minute, 
ihe TSA Reynier plates were incubated 2k hours and a representative of all mor- 
phologically different isolates was picked for identification. 

Surface areas k inches square (l6 Bqvialce inches) in the food management and 
hygiene compartments were swabbed with Trypticase Soy Broth (TSB) moistened 
swabs, and the specimens were passed out and plated to blood agar, MacConkey's 
Agar, Staphylococctis #110 Medium, TSA, and Sabouraud Dextrose Agar. 

Post-test swabs of selected hardware and equipment surfaces were plated to 
the appropriate media to recover aerobic and anaerobic bacteria and> fungi . Com- 
ponents of life support siibsystems (such as charcoal and particTzlate filters) 
were inoculated to TSB and Brewer's Thioglycollate Broth for initial incubation 
and then plated to the differential and selective media. 

OBJKJTIVES 



The following determinations constituted the dermal and enviroiamental 
microbiological objectives of the 90-day test: 

(1) Gross quantitative shifts in aerobic and anaerobic dermal flora of the 

skin sites 

(2) Qualitative alterations in the composition of the microbial flora of 

individual skin sites 

(5) Exchange of flora between crewmen or between dermal sites 

(k) Counts and types of environmental microbiological contamination 

RESULTS 

Ho significant quantitative alterations were foimd in dermal aerobic or 
anaerobic bacterial flora or in the fungal flora. Tery consistent growth scores 
on the primaiy isolation media were obtained thro-ughout the 90-day test. 

518 



There were no oTjservable shifts in the predominant dermal isolates throu^- 
OTit the nm. Staphylococcus epidermidis was recoTored from each site of each 
crewnKin on eveiy sampling period. Other members of the dermal flora were iden- 
tified as members of the genera Micrococcus, Corynehact e r ium , Bacillus , Sarcina, 
and Aerococcus . Gram negative enterics, tisually E. coli , were recovered, pri- 
marily from the perineal region. 

Two dermal legions, the axillary and perineal, eaJiiMted microbial profiles 
imiq[ue to each crew meniber. These profiles were maintained throughout the test _, 
and no exchange among the crewmen or their indiridual skin sites was noted. The 
interdigital spaces of all four crewmen were consistently similar in their aero- 
bic floral composition. These findings are also illusti^ted in the recovery of 
obligate anaerobes from the skin sites. 

Table I indicates the number of obligate anaerobes recovered from each sam- 
pling period and dermal site. The axilla and perineum of all crewmen consis- 
tently yielded anaerobes, preliminarily identified as "anaerobic diphtheroids". 
However, the toe web of each crewman remained conspicuously absent of obligate 
anaerobes. The perineum of crewman h consistently yielded, in addition to 
anaerobic diphtheroids, large numbers of Bacteroides melanogenicus . 

Staphylococcus aureus has been the subject of many epidemiological studies, 
including those conducted on Apollo astronauts. This potentially pathogenic 
microoa^anism is carried by a large percentage of the population, primarily in 
the nasal region. It has been recently revealed tlmt the skin, especially the 
perineal region, alsro harbors S_. aureus . Tabie U shows data indicating the 
sporadic presence of this organism on all skin sites. Coagulase positive 
S. aureus isolated from Tellurite Glycine Agar at MDAC's laboratory are indi- 
cated by a +. Marmitol positive, coagulase positive or negative S^. aurevis 
identified as such from isolates sent to Langley Research Center are indicated 
by 0, Although crewman 2 remained the predominant nasal carrier of S. aureus 
throxighout the test, crewman \ yielded this organism from skin sites most 
frequently. 

Microorganisms shed from the skin of inhabitants of closed environment are 
an important source of atmospheric and surface contamination. Therefore, it 
is not surprising that the predominant member of the crewmen's skin flora. 
Staphylococcus epidermidis , was also the predominant isolate from the simulator 
air and surfaces. To cocrplete the epidemiological study utilizing S. aureus , 
contamination by this organism was also followed in the air and on the surfaces. 
Table III indicates the dates of recovery from each sampling site. Whether or 
not the source of this contamination was generated by the crewmen's dermal 
S. aTxreus or those residing in their nasopharynx remains open to speculation, 
since phage and antibiotic-resistance typing proved unsuccessful. 

Figure 2 illustrates the microbial counts obtained from Reynier air sam- 
ples. Atmospheric counts remained low (less than 3 microorganisms /ft^ of air) 
throughout the test. Precounts and postcounts were extremely low (less than 
0.2 microorganisms/ft5 of air) indicating that the crewmen were the sole soxurce 
of atmospheric contamination. During the period that the catalytic toxin burner 
remained inoperative, atmospheric counts rose slightly in the forTra,rd section 

519 



(where the 'burner was located); however, aft section counts dropped or remained 
the same. Pungal counts remained extremely low In "both sections throughout 
the test. Maximum counts occurred on the ^6th test day and consisted of 
0.12 organisms /ft^ of air In the forward section and 0.25 orgajilsms/ft^ of air 
In the aft compartment. 

Although the catalytic "burner shutdown did not Influence microbial air 
counts significantly, figure 5 Illustrates a coinciding Increase In the nxmiber 
of different "bacterial types Isolated from the air of the forward compartment. 
Microorganisms identified as Alcallgenes sp ,, Keisseria catarrhalis , 
Enterohacter Group B and Proteus mirahilis were not Isolated from the air 
before the 10th week of the test. Whether or not this Increase In bacterial 
types represents a natural buildup of bacterial species or is a result of the 
Inoperation of the catalytic burner remains open for further investigation. 
The latter seems unlikely. 

Figure k illTistrates bacterial surface counts from the food management and 
hygiene areas. Bars which extend to 30 organisms /in^ of surface area represent 
plate scores which were too numerotis for accurate coxmting. Significant build- 
ups of contamination occurred on six occasions in the crew hygiene area. Fungal 
co-unts were als^o high in the hygiene area in comparison with the food management 
area. Ho fxmgi were Isolated in the food management area until midway through 
the test, and the count remained low until test completion. 

Listed in decreasing order of occurrence in table IT are the predominant 
bacteria contaminating the surfaces . Staphylococcixs epldermldis was recovered 
on every sampling date, excepting one, from both the food management and the 
hygiene areas. Species of Bacillus were the next most common Isolate followed 
by the gram positive Sarclna and Micrococcus . Gram negative bacteria were com- 
pletely restricted to the hygiene area except on ik July when all three types, 
Aerobacter , Alcallgenes , and Pseudomonas were found In the food management area. 
nSais gram negative contamlnatldn coincides with the only significant contamina- 
tion buildup in the food management area which also occxir3?ed on ik JrOy. 

Figure 5 shows the areas investigated durii^ the post-test microbiology 
study. Organisms in all three categories were recovered. At this writing, 
isolates are being Identified and analysis of the results will begin as soon 
as identifications are completed. 



520 





z 




Sp 


CM €M ^ 


O •— 1 C? 


i-H ,— 1 CD 


i-i CO CD 






^ </^ 












Ul 




^ yj 
J— 












S 
^ 






f— • 1— « O 


f-H •— 1 O 


CM r-4 ^ 


1— 1 ^ ^ 




m 




O- 












oc 




^ ^ 


^^ Csl 1-4 


CM 1— 1 ^ 


r— 1 1— 1 ^ 


I— 1 en 1— 1 




o 




o> 












u. 




s 


CM O O 


I— 1 I— 1 ^ 


CM ITS ^ 


cr» crv ^ 




O 




oo 












CO 




oo 












Ul 




ci 


O r-« O 


O i-H C3 


r-H CD ^ 


CM tn CD 




t 




oo 












O) 


o 
5: 


1— 1 


I-H l-H ^ 


CD 1— t ^ 


1— 1 1— 1 O 


i-H ^- ,-J 




J 


1— t 


oo 












< 


•z. 














C3C 


o 

1— 
o 


5 
oo 


CM CM CD 


f— 1 1— 1 C3 


c^ r-H cn 


CM -«* ,-H 




Ul 
O 


UJ 

—I 

8 




CM i-i O 


O r-H O 


CM CD i-H 


r-H <n O 




S 


o 


jt! 










HH 


o 


fe 




CM CM ^ 


•— 1 i-H C3 


•-• o o 


•— 1 cn o 


^ 


(K 


LU 










i-:i 


u. 


H- 


'd- 










m 




<c 


i::! 


i-i CD O 


i-< ^ CD 


«M CD O 


r-l CTk O 


< 


O 


o 


r— 










H 


Ul 

1- 

3 


















c= 


1— 1 I— 1 1— 1 


CD •— 1 ^ 


O O O 


.-• CTi O 






r— 












o 




S 


1— * i-H ^ 


O r-< O 


CM O O 


CM m ^ 




i/i 




NO 












^■B 
















m 




S 


r-l .— 1 ^ 


CD .-< O 


r-H 1— 1 ^ 


o ^ o 




Ul 




vO 












OQ 




^E 












O 




'=t'€^ 


^ 1 1 


r-4 CD O 


CD O O 


^ cr\ .-H 




Ul 
















< 
z 
< 

Ul 






1 t-H ,-1 


■-4 CM CM 


^ O r-l 


CD ^^ CM 




o 

Ll-I 




=> as 


=3 QQ 


R «a 




1- 

< 


SITE 
MPLI 


gis 


gig 


gss 


gss 




r: Q^ lAJ 


rr ck: LU 


Tl^. *JJ 


— Qi LU 




<c 


X LU o 


X liJ o 


X tZi O 


X LU o 




OQ 


t/j 


< Q. 1— 


< Q. h- 


< ex. H- 


< Q- 1— 




1 












o 


REW 


r-4 


CM 


cn 


^ 






c 


> 











521 



m 
< 



O 

UJ uj 



CO 



ui 



CL ly 
ft 
UL —I 

o < 

> o 

o 

o 

tr 



o 



O 



o 
o 



UJ 

t— 






as ,- 

O^ CO 

o 

IfN 
OO 
OO 

en 

OO 



OO 



OO 



?3 






o 

so 

^^ 
^ t 

Q. Q- 
nO ^^ 



C3 O O 



I I I 



+ I I 



I O I 



I O ^ 



I I O 



C3 I C3 



I I I 



I + 



LU 



CO 



O 
LU 



< 
CO 



O 




I I 



I I 



I I 



UJ UJ 



— a: UJ 
X UJ o 

< D- I— 



CM 



+ + 



I I 



I ^ 




O I CD 



I 




I 




Cf\ 



I 
I 



CD 



—■ Qi UJ 

X UJ o 
< Q. I— 



o S -c 

Q " fe 
^ a: o 

S ZJ CQ 



+ o 



522 



UJ Hi 



(/> 



tr s 






B 

Eh 



o 9 
o < 

P UJ 

d ^ 

CL CL 

< C/> 

H O 
(/> ^ 

O < 
>- i/i 

UJ CO 

O S 
O o 

UJ QC 



o 

I— 
o 



o 
o 



< 



as 






oo 



oo 
oo 



oo 



oo 



13 






'St 

erf 






s 

NO 

vO 

1— « 



NO 



o 

—J LU 

^ to 



I 

I 

+ 

I 



o 



UJ 

:s 

LU 

o ^ < u. 
O 5 «jJ Qs: 
5 :S Qi => 
u_ S < O) 



+ 
I 

+ 

+ 

+ 



Z <-> 

LU < 

O L^ Q£ 
>- Qi =3 
3= < CO 



I 

+ 
I 
I 



I 

+ 
I 

I 



a. Q_ ^ 

o o — ,v 
LU o < ii; 



I 
I 

+ 

I 

I 



on 

< 

LU S Qi t 

a; o — ^ 
o o < S 



525 






< 

Z 



< 

O 
O 

UJ 
O 

< 



CO 
CO 



O 
O 

UJ 

ir 





































E 


+ + 


1 1 


1 1 




1 


1 1 


1 + 






d 
















. 




§ 


+ + 


1 + 


1 i 




1 


1 1 








^ 


+ + 


1 1 


+ + 




+ 


1 1 








lO 




















C! 


+ + 


1 + 


1 1 




+ 


1 1 








as 




















00 




















^ 


+ + 


+ + 


1 1 




1 


1 1 








00 




















^^ 




















5; 


+ 1 


+ + 


+ + 




1 


1 + 




1 + 


a 


eo 


















r« 






















5 

OB 


+ + 


+ 1 


< -^ 




+ 


1 + 




1 + 


> 




















cs 




















Ul 

> 
o 
u 


•a 


+ + 


+ 1 


1 1 




+ 


1 1 


1 + 


1 + 


lU 




















cc 




















o 


5 


+ + 


+ + 


1 1 




1 


1 1 


1 I 


1 1 


lU 


f«» 


















1- 




















< 




















a 


* 




















5: 


1 + 


1 + 


+ 1 


+ 


1 


1 1 


+ + 


+ + 




p» 




















^ 


+ + 


1 + 


1 1 




1 


1 1 


1 + 






i 


+ + 


1 t 


t 1 




1 


+ + 


1 + 






ft 




















ti 


+ + 


+ 1 


+ 1 




+ 


+ + 


t 1 






IS 




















(B 




















c 


+ + 


1 1 


1 1 




1 


1 1 


1 1 






10 




















§ 


+ + 


•f 1 


+ 1 




1 


1 r 


1 1 






t 


t- 


g 


»- 




1- 


V- 


»- 




Z 


wt 








z 


z 




Ul 


Ul 


UJ 


Ul 




UJ 


UJ 


Ul 


Q 


Sg 


^s 


S!< 


i 


< 


UJ < 


s< 


s< 


ca uj 


C9 U< 


O UJ 


C9 


UJ 


(9 Uj 


eg UJ 


eg Ul 


Ul -J 


< 5 


< 55 


< s 


< 


EC 


< s 


< !E 


< oc 


k£ 


« < 


z < 


z < 




< 


z < 


52 


Z < 


M ^ 


< UJ 


< Ul 


< Ul 


< 


Ul 


< UJ 


i^ 


S H; 


S as 


'S z 


Z 


z 




Z Z 


CO 


a^ 


«=»s 


a'H. 


a 


Ul 


ol 


a!£f 


q!±! 




o o 


o u 


O C9 


o 


5 


O C9 


O <9 


O C9 




o > 


o > 


O > 


o 


>■ 


O > 


O >■ 


O > 




u. X 


U. X 


U. X 


li. 


X 


U. X 


£ X 


u. X 




M 




















U 

O 

o 


















31 


CO 






K 




3 




M 

Ul 




S 






< 

(9 

EC 
O 


u 

o 

>■ 

1 


a 
1 

Ul 

o 
a! 

Ul 


M 

3 

mi 

< 

oa 


8J| 


< 

o 

K 

3 


4 


Ul 

O 

K 
Ul 

< 


8i| 


U 

u 

o 
u 

o 
oe 
u 

i 


fti 


Ul 

o 

< 

< 


8il 


z 
o 
Z 
e 

.a 

1 


8i| 



524 



gc 


(/) 


o 


S 


^ 


< 





—1 




^ 


Ill 


<£1 


T' 


c? 


ill 


to 




c^ 


O 


UJ 


>- 


Q. 







1 






UJ 




UJ 


o 




1— 


< 


1— 


to 

i 


i 


g 

S 




1— 


o 




o 


CO 


Ixl 

1— 


PUN 
ARD- 


< 

UJ 


UJ 

o 

,< 


t/> 


> 


31 a: 


Q^ 


o < 


ILI_ 


^ 


ZD 


a. oo o 


^ 


to 








a: 


rj 


UJ 


^ 


2:^1 


-J 


>- oo 


DC 
1.1 1 


<r 


p^ 


0£: 


1— 


P 


UJ 


—•1 


O 


o 


^ 


O <| 


o. 


3: 


" 













>■ 






_J 






X 




to 


1— 




UJ 


2r 


to 




o 


=) 


o 


S 


Q^ 


=3 


> 


1— 

to 


CQ 





UJ 

to 
o 



g 

DC 

X 



to 



s 


o 

UJ 




=3 


Q£. 


O 


Ql O 
UJ I— 


O 


to 


to 


1 



o 
o 
o 

-s 

u 

be 

■r-l 

s 

CQ 



U 

u 



bfi 
•I-l 



525 









- — 


_ ^ 


_— ^ 


/^ 




- 


^ 


\ 




^ 


SHUTDOW 
1 


A 




BURNER 
1 








"«** 

^ ^ 


ATALYTIC 
1 




FORWARD SECTION 

(EQUIPMENT) 

--AFT SECTl ON (CREW) 






<>^ 


1 






\ 















\r\ 









m 



cr» 



It I 

E«>o 
yjoo 



E 



CO 
CQ 

o 






o 

(0 



o 
o 



42 

o 



I 



P^ 



C^k 



evi 



yiv JO iood oiano y3d swsiNVoaooHOiw Jo y3awnN 



526 




CQ 
CQ 



U 

o 



-M 

o 



m 
a 



00 



|xi 



UJt/> 



CM 



a3uiiN3ai S3ciAiiviy3iDva jo mmm 



527 



LU 



o ;z a o 

o s "^ >- 



1 



D 



^^^^^s 










c 



so 







CQ 


1—4 




0) 








CM 




^ 






03 


oo 




TO 


oo 




CZ2 


c:; 




M 


oo 






r-H 




S 


OO 


CD 


O 

u 




o^ 


02 


5 


f— 1 


-w 


oo 


^ 


p 




o 


b 


83 


P 


u 


1— 1 


o 

LU 

1 

,. 1 


a 


£ii 


o 


4-^ 


r*- 


o 


o 




fe 




1^ 


Jj 


• 


1^ 


< 








NO 




N 






1 



1 



1 



1 



1 



9 

so 

NO 



a: 

vO 



CM 



oo 



83 S S3 S s:ij 

Bovjyns do honi ayvnbs y3d swsiNvoao do mmm 



528 




d 
o 

.1-4 

•i-i 

a 
■s 

O 
o 







t/1 






1— 




t/) 


22: 


UJ 

g 


UJ 


LU 


a. 


^ 


>-s 




CO 







O to 

t/1 O LU 
O < z 

s ^ o 
^ o z: 



to 

LU 



< 
Q- 



U 

o 

•r-t 

a 

u 
o 

bD 
I— I 

i 

CO 






85 



to 



^ 


H- 













ill 




1— 


Q- 


LU 


to 







if 


g 


LU 




OC 


ill 


;z 


0^ 


d 


< 




to 







r— UM ^mmm 

L- ^ 5 ^ fc 



o 



to 

III 

o 
o 



to o 

Z LU 

13 — J 
CO CQ 

LU "^ 
O Z 

z o 



LU 



to 

oe: 






LU 
>< 



iSoo 



O. O 
to O 



O 



UJSS 



OC 



< o 

LU <- 

tO OC 
-J uj LU 

q; Zj o 
=> o o 



to 
I— 
o 

o 

8 

to QC 
lD Z LU 

< O^ 
LU _J ^ 

O LU 



~ G5 ^ Of: 

Q^ t^ ^ LU 






o 

QQ 



=3 



t/> »- Q 
• • • 



I 

O 

> 



^ o o K 
^ S o ^ 

< O iD (/) 
> o X a. 






10 

1X4 



529 



NASOPHARIMGEAL STUDIES 

By Judd E. Wilkins 
NASA Langley Research Center 



SUMMARY 




Before and after the test and -weekly during the test^ nose and throat swabs 
from each cre-wman were cixltiired for Staphylococcus aureus , beta-hemolytic 
streptococci, neisseria meningitidis , Diplo coccus pneumoniae and Hemophilus 
influenzae . Pretest studies indicated that crewman 2 was a permanent nose and 
throat carrier of S . aureus . On the fourth day of the test S . auretis was 
recoTered from the nasopharynx of the other three crewmembers and was retained 
by them during the test and in posttest samples. Failure to obtain a phage type 
or antibiotic sensitivity "marker" for these strains precluded identifying the 
source of spread of S. aureus within the simulator. Beta-hemolytic streptococci 
were isolated from the throat of crewman 1 only on the fourth, 6oth, and 67th 
days of the test. Prophylactic erythromycin was administered, and the organism 
was not recovered during the remainder of the test or from posttest samples. No 
interpersonal transfer of this organism occurred. Neisseria meningitidis was 
recovered from the throat of crewman 5 during pretest sampling, throughout the 
90-day test, and from posttest samples. Ihis organism was also recovered from 
the throat of crewman 1 on the 25th and 52d days of the test, but failixre to 
ascertain its specific serological type precluded determining if it had been 
acquired from crewman 3. N. meningitidis was not recovered from the throat of 
the other two crewmen. All four crewmen were healthy carriers of Diplococcus 
pneumoniae , and it was consistently isolated from the throat during the 90-day 
test. All attempts to recover Hemophilus influenzae failed, and no effort was 
made to culture this organism after the 53<3- day of the test. In the 90-day test 
there was no clinical illness related to the carriage or transfer of potentially 
pathogenic bacteria. It is recommended that in future simulator tests a series 
of experiments be performed on the transmission of microbial agents and the 
effect of the environment on immxinoglobulins and other defense responses. 



INTRODUCTION 



A ntraiber of studies of volunteers in test chambers which simiilate certain 
aspects of spaceflight have been made and the results of these tests have been 
reviewed in the National AcadenQr of Sciences report "Infectious Disease In 
Maimed Spaceflight." (See ref. 1.) Even though the microbiological results 
have varied from test to test, it does not appear that the closed environments 
of these simulators significantly affect either the h-uman microflora or the 
host-parasite relationship. In order to determine, in part, if this pattern 
woxxld be followed in the 90-day test, the following bacteria of the nasopharynx 
were selected and cultured on a weekly basis: Staphylococcus aureus, 

531 



beta-hemo lytic streptococci^ Neisseria meniiigitidis , Piplococcus pneumoniae , 
^^^ Hemophilus influenzae . Because the health and. welfare of the crewmen was 
of prime consideration in selecting these potentially pathogenic "bacteria^ the 
opportunity was also presented for studying the epidemiology of the interper- 
sonal transfer of pathogens. 



MAEEEIALS MD MEIHODS 



Prior to the 90-^^7 manned test, the crewmembers were trained in sterile 
techniques and the proper procedures for taking nose and throat samples. The 
four crewmen were divided into two teams j each member of a team was responsible 
for obtaining swab samples from the other member of the team. Nasal samples 
were obtained by Inserting a sterile, saline -moistened swab about l/2 inch into 
either the right or left anterior nostril and swabbing the inner surface three 
to four times in a circular pattern. A separate swab was used for each nostril. 

Throat swabs were taken with the crewman seated, his tongue depressed, and 
the throat well ejcposed and illuminated. The swab was rubbed firmly over the 
back of the throat, both tonsils or tonsillar fossae, and any areas of inflamma- 
tion or exudation. Care was taken to avoid touching the tongue, lips, or cheek 
with the swab. 

The nasal swabs were streaked onto commercial blood agar and plates of 
Staphylococcal Medium 110 and incubated for 2k- hours at 37° C. Colonies which 
morphologically resembled Staphylococcus aureus were transferred to Trypticase 
Soy Broth, incubated for 2k- hours at 37° G, and tested for coagulase by mixing 
equal volumes of broth culture and citrated rabbit plasma diluted 1:5. Th§ 
tubes were incubated at 37° C for 2k- hours and inspected at k and 2k ho-urs for 
clotting. All coagulase positive cultures were sent to Dr. Harry Dalton* for 
phage typing. 

The throat swabs were streaked onto Field's Enrichment Agar for Hemophilus 
Influenzae , Thayer-Martin plates (prewanned to 37° C) for Neisseria meningitidis 
and blood agar for bet a-hemo lytic streptococci and Diplococcus pheximoniae . 
Field's medium and the blood agar plates were incubated for 2k hours at 37° Cj 
the (Thayer-Martin plates were incubated in 5 to 10 percent 002- The Field 
plates were observed for the typical growth of H. influenzae , and the number of 
colonies and brief colonial description were recorded. N. meningitidis was 
identified by Gram stain, colony morphology, the oxidase test, sugar fermenta- 
tions, and serological typing. Optochin disks were used to differentiate between 
alpha streptococci and D. pneumoniae , and bacitracin disks were used to desig- 
nate the bet a-hemo ly-tic streptococci as probably belonging to Group A. The 
elapsed time between taking the swab samples and plating on primary isolation 
media was less than 1 hour. 



■^Department of Clinical Pathology, Medical College of Virginia, Richmond, 
Virginia. 

532 



RESULTS 

"Staphylococcus aureus" 

During pretest baseline studies, Staphylococcus aureus was isolated from 
the nose and throat of cre-wman 2 only, and not from the other three crewmen. 
Previous microbiological studies d-uring a 5-clB,y checkout of the space-station 
simulator strongly indicated that crewman 2 was a permanent carrier of S. 
aureus . The first swab samples, which were taken k days after the crew entered 
the simulator, indicated that S. aureus was recovered frcan the throat of crew- 
men 1 and 5 and from both the nose and throat of crewman ^l-. (See table l). 
During the 90-day test, S. aureus was recovered only four times from the throat 
of crewman 1, consistently from the nose and throat of crewman 2, twice from the 
nose of crewman 3 and consistently from his throat, and sporadically from the 
throat of crewman k and rather consistently from his nose. It could not be 
determined if the strains of S. aureus recovered from crewmen 1, 2, and 3 
originated from crewman 2 because all attempts to phage-type these isolates 
were unsuccessful. In addition, antibiotic sensitivity tests failed to show 
any unusual patterns, as all isolates were sensitive to the ma;5or antibiotics. 
IBius, failure to obtain a phage or antibiotic "marker" for these strains pre- 
cluded identifying the soiirce of the spread of S. aureus within the simulator. 
At this time, therefore, it can only be speculated that crewman 2 was the pos- 
sible soxjrce of this organism. 

Beta-Hemolytic Streptococci 

On the fourth day of the test beta-hemolytic streptococci were isolated 
from the throat of crewman 1 only. (See table II.) This organism was not 
recovered during the next 7 weeks from this crewman but was cultxired again on 
the 60th and 67th days of the test. At that time erythromycin was administered 
as a prophylaxis, and the organism was not recovered during the remainder of 
the 90-day test or from the posttest samples. It is interesting to note that 
crewman 1 was also carrying S_. auretis in his throat at the time erythomycin was 
administered, and even thovigh this organism disappeared during antibiotic treat- 
ment, it did reappear at the end of the test and in the posttest samples. 

"Neisseria meningitidis" 

Pretest samples from the crewmen indicated that one crewman (3) was a 
healthy throat carrier of N. meningitidis . (See table III.) This crewman 
carried this organism in his throat throughout the 90-day test, and it was also 
recovered from posttest samples. Ueisseira meningitidis was also recovered from 
the throat of crewman 1 on the 25th and 32d days of the test. However, as type 
specific typing was not performed, it is difficult to determine if a transfer 
of N. meningitidis took place between these two crewmen. This organism was not 
isolated from the other crewmen. 



535 



Dtiring the pretest studies and the first two veeks of the test, there were 
relatively few colonies of W. meningitidis on the Thayer-Martin plates from 
crewman. 3« Starting ahout the 25th day of the test, the number of colonies 
increased, and on three occasions the growth was confluent. Serological typing 
revealed that the initial isolates were type C, hut on the 60th day of the test, 
type B as well as type C organisms were isolated. It is possihle that this 
crewman was a carrier of hoth types of N. meningitidis . 

"Diplococcxxs pneumoniae" 

As indicated "by the pretest studies, all four crewmen were healthy carriers 
of D. pneumoniae . (See tahle TV.) During the coixrse of the 90-day test, D. 
pneumoniae was consistently isolated from the throat of all crewmen, althoxjgh 
on occasions skips occurred in which the organism was not recovered. The 
cases involving negative cultures were followed hy isolation of the organism 
from the next weekly samples. D. pneimioniae was isolated from all posttest 
samples 28 days after termination of the test. 

"Hemophilus influenzae" 

All attempts to recover H. influenzae from the throat of crewmen failed, 
and no effort was made to dulture this organism after the 53^ day of the test. 

Discussion 



There were a number of factors associated with the 90-day test which made 
it unique so far as the microhiological studies were concerned. Of paramount 
importance was the fact that a realistic closed environment was ohtaihed, as 
there was no penetration of the chamher diiring the test and only a weekly pass- 
out of biomedical samples throijgh a presterilized autoclave. In all previous 
tests of space-station siirailators , various degrees of penetration of the simu- 
lators occurred in order to pass in equipment, spare parts, food, and so forth. 
Prior to the 90-day manned test th6 crewmen did not undergo an isolation or 
quarantine period to pennit acute disease to express itself or to exchange flora; 
therefore, the microbial ecologsr inside of the chamber consisted of each crew- 
man's own "off-the-street" organisms plus those microorganisms Indigenous to 
the chamber. Another important factor was the rapid processing of samples which 
permitted the recovery of fastidious organisms such as N. meningitidis . The 
goal here was to minimize procedural effects on any microbial alterations that 
might occur during the test. Plnally, since the major objective of the 90-day 
test was the engineering development of life-support subsystems, the crew was 
exposed to regenerative systems and space-type living conditions. The key fea- 
tures of these systems were: potable water recovered from urine and humidity 
condensate, oxygen obtained from the reduction of CO2 and the electrolysis of 
water, a prototype waste management system based on the "slinger" concept, mini- 
mal personal hygiene facilities consisting primarily of body wipes, and an 
atmosphere of 10 psia (5.1 psla oxygen and 6.9 psia nitrogen). All these factors 

53^ 



and others, either alone or in coaibination, must be considered as they affect 
the total microhial ecology inside the chamber. 

A ntnrtoer of studies on man in closed environments have "been conducted, and 
the resiilts are summarized in the National Academy of Sciences report, 
"Infectious Disease in Manned Spaceflight." (See ref. 1.) Based on a litera- 
ture search, the following two conclusions presented in that report are impor- 
tant as they relate to the microhiological findings of the 90-day test: 

"Inteirpersonal transfer of "bacterial pathogens occurred occasionally "but 
did not result in clinical disease, except in the case of oufbrealcs of respira- 
tory (viral?) disease in submarine crews and in occupants of the underground 
shelter. In several instances transmission of respiratory and enteric bacteria 
of potential pathogenicity did not, occur even under conditions of extreme 
crowdedness." 

"Although few exceptions occurred which are difficult to evaluate, most 
of the results reviewed here suggest that the conditions of spaceflight, as 
simulated by these studies, and for the time intervals tested, will not signifi- 
cantly affect either the microorganisms of the h-uman environment or their hosts 
to cause a shift in the normal host -parasite equilibrium." 

As will be pointed out in the following discussion, the results of the 90-day 
manned test , are in agreement with these two conclusions. 

Although it was not possible to "tag" the strain of S. aureixs recovered 
from crewman 2, it is reasonable to assijme that the spread of this organism 
originated from that crewmember. If this is the case, then the subsequent 
spread, which did not res\ilt in clinical disease, is in agreement with the 
findings of other closed-environment studies (refs. 1 and 2). Beta-hemolytic 
streptococci were isolated sporadically from crewman 1, and prophylactic 
erythron^rcin was administered on the 67th day of the test. Kiere was no evi- 
dence of Interpersonal transfer of this organism or the development of clinical 
disease . , 

Ihe findings of Neisseria meningitidis are of Interest because this organ- 
Ism has not been reported from other closed-environment studies. Althou^ one 
study reported that Neisseria were recovered from four men in a closed system, 
the species was not identified. (See ref. 3«) In the 90-day test, crewman 3 
entered the chamber carrying type C N. meningitidis , maintained it in his throat 
throughout the test (type B was recovered in the latter stages of the test), and 
in posistest samples. Again there was no evidence of inteipersonal transfer of 
the organism or the development of clinical disease. All four crewmen were 
healthy carriers of D. pneumoniae , and clinical disease did not develop. 

It has been speculated that the close confinement of Tmxx in space-station 
simulators for prolonged periods of time could represent a serious threat to 
their health. Some factors influencing these speculations include inadequate 
filtration and contamination by sneezing, coughing, or touch, since it is well 
established that transmission of a number of infections is by direct contact 



535 



and that the risk of infection is inversely related to distance (ref. l). 
Perhaps the most interesting microhiological finding to emerge from the 90-day 
test is that nothing of serious significance occurred, either to the host flora, 
or to the host-parasite relationship leading to clinical disease. These 
findings generally support the olsservations ohtained from other closed-chamber 
environmental studies (ref. l). The reasons for these apparently "negative" 
results are not clear at this time, and the role some factors may play in these 
simulator studies can only he speculated. In the case of the 90-day test, three 
organisms were potentially pathogenic, and yet no serious clinical effects 
occurred. It could he that space simulators are not the hostile environments 
that many thought they might he, and in fact, the crevmen adapt rather quickly 
to these new environments. Although these results are encouraging, it must he 
pointed out, as it was in the National Acadeiry of Sciences report (ref. l), 
"...a series of negative results is not a safe "basis for extrapolation." It 
should also he pointed out that the 90-day test concerned itself primarily with 
aerohic hacteria with minor emphasis on the anaerobes. Mycoplasma, and viruses. 
Future simulator tests should emphasize these orgapisms in order to satisfy the 
requirement that a spacecraft environment will not caxose any adverse effects 
for all groups of microorganisms. Finally, there are still a nvmiber of unknown 
factors associated with actual spaceflight which, could markedly alter the normal 
host-parasite relationship. One of the more important factors is the lack of 
gravity on (l) the deposition of particles in the respiratory tract and (2) the 
interpersonal transfer of microorganisms. A continuing research program will 
he needed to provide answers to these and other questions. 

CONCLUDING REMARKS 



Before and after the test and weekly during the test, nose and throat swabs 
from each crewman were ctilt'ured for Staphylococcus aureus , beta-hemolytlc 
streptococci. Neisseria meningitidis , Diplococcus pneumoniae , and Hemophilus 
influenzae . Pretest studies indicated that crewman 2 was a permanent nose and 
throat carrier of S. aureus . On the fourth day of the test S. aureus was 
recovered from the nasopharynx of the other three crewmen and was retained 
by them during the test and in posttest samples . Failure to obtain a phage type 
or antibiotic sensitivity "marker" for these strains precluded identifying the 
so\irce of spread of S. aureus within the simulator. Beta-hemolytic streptococci 
were isolated from the throat of crewman 1 only on the fourth, 6oth, and 67th 
days of the test. Prophylactic erythromycin was administered, and the organism 
was not recovered during the remainder of the test or from posttest samples. No 
interpersonal transfer of this organism occurred. Neisseria meningitidis was 
recovered from the throat of crewman 3 during pretest sampling, throughout the 
90-day test, and from posttest samples. This organism was also recovered from 
the throat of crewman 1 on the 25th and 52d days of the test, but failure to 
ascertain its specific serological type precluded determining if it had been 
acquired from crewman 3» N. meningitidis was not recovered from the throat of 
the othey two crewmen. All four crewmen were healthy carriers of Diplococcus 
pneumoniae , and it was consistently isolated from the throat during the 90-day 
test. All attempts to recover Hemophilus influenzae failed, and no effort was 
made to ciilture this organism after the 53d day of the test. In the 90-day test 



536 



there was no clinical illness related to the carriage or transfer of potentially 
pathogenic "bacteria. It is recommended that in future simulator tests a series 
of experiments he performed on the transmission of microbial agents and the 
effect of the environment on immunoglohulins and other defense responses. 



KEZEREailCES 



1. Space Science Board: Infectious Disease in Manned Spaceflight — Prohahili- 

ties and Gountermeas-ures . Nat. Acad. Sci.-Nat. Res. Counc; 1970. 

2. Moyer^ James E.j and Lewis ^ Y. Z.: Microhiologic Studies of the Two-Man 

Space Cahin Simulator: Interchange of Oral and Intestinal Bacteria. 
SM-TDR-6if-3; U.S. Air Force, Mar. 196i|-. (Available from DDC as 
AD h^9 097.) 

3. Riely, Phyllis E.; Geib, Donna; and Shorenstein, Diane: Determination of 

the Indigenous Microflora of Men in Cont3?olled Environments . 
AMRL-TR-66-33, U.S. Air Force, Apr. 1966. (Available from DDC as 
AD 656 9k6.) 



557 



TABLE I 
RECOVERY OF STAPHYLOCOCCUS AUREUS 
FROM THE NOSE AND THROAT OF CREWMEN 



CREW- 
MAN 


SITE 
SAMPLED 


PRE- 
TEST 
DAY 


TEST DAY 


POST- 
TEST 
DAY 


-4 


4 


11 


18 


25 


32 


39 


46 


M. 


60 


67 


74 


81 


88 


+18 


1 


NOSE 
THROAT 


:•. -' 


+ 


■ * V' 


■ ■- ■" 


-;■ 


,,- 


:■;-•; 


:''' ■ 


' .■-■',: 


;: - :■' 


+ 


: '^^ ■... 


-.*: 


+ 


+ 


2 


NOSE 
THROAT 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+, 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


+ 
+ 


3 


NOSE 
THROAT 


- 


+ 


+ 


+ 


+ 
+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 

+ 


+ 


+ 


4 


NOSE 
THROAT 


- 


+ 
+ 


- 


+ 
+ 


+ 
+ 


+ 
+ 


+ 


+ 


+ 


+ 


+ 

+ 


+ 


+ 
+ 


+ 


+ 
+ 



- NOT RECOVERED 
+ RECOVERED 



TABLE II 
RECOVERY OF BETA-HEMOLYTIC STREPTOCOCCI 
FROM THE THROAT OF CREWMEN 



CREW- 
MAN 


PRE- 
TEST 
DAY 


TEST DAY 


POST- 
TEST 
DAY 


-4 


4 


11 


18 


25 


32 


39 


46 


53 


60 


67 


74 


81 


88. 


+18 


1 


- 


+ 


- 


- 


- 


- 


- 


- 


- 


+ 


+ 


- 


- 


- 


- 


2 


- 


- 


- 


- 


- 




- 


- 




- 


- 


- 


- 


- 


- 


3 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


4 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 


- 



- NOT RECOVERED 
♦ RECOVERED 



558 



TABLE III 

RECOVERY OF NEISSERIA MENINGITIDIS 

FROM ThE THROAT OF CREWMEN 



CREW- 
AflAN 


PRE- 
TEST 
DAY 


TEST DAY 


POST- 
TEST 
DAY 


'4 


4 


11 


18 


25 


32 


39 


46 


53 


60 


67 


74 


81 


88 


+18 


1 


- 


- 


- 


- 


+ 


+ 


- 


- 


- 


- 


- 


- 


- 


- 


- 


2 


- 


- ■ 


- 


- 


- 


- 


- 


- 


-' 


- 


- 


- 


-_ 




- 


3 


+ 


+ 


+ 


++ 


+++ 


+++ 


■H+¥ 


++ 


+++ 


+++ 


+++ 


+++ 


-H-H- 


++-H- 


+ 


4 


- 


- 


- 


- 


- 


- 


- 


-■ 


- 


- 


- 


- 


- 


1 


- 



- NOT RECOVERED 
+ RECOVERED 



DEGREE OF GROWTH 
10 to 100 + 
100 to 300 ++ 
300toTNTC +++ 
CONFLUENT 



TABLE IV 
RECOVERY OF DIPLOCOCCUS PNEUMONIAE 
FROM THE THROAT OF CREWMEN 



CREW- 
AAAN 


PRE- 
TEST 
DAY 


TEST DAY 


POST- 
TEST 
DAY 


-4 


4 


11 


18 


25 


32 


39 


46 


53 


60 


67 


74 


81 


88 


+18 


1 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


- 


+ 


+ 


- 


+ 


+ 


2 


+ 


+ 


+ 


+ 


- 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


3 


+ 


+ 


+ 


+ 


+ 


+ 


- 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


+ 


4 


+ 


+ 


+ 


+ 


+ 


+ 


. + 


+ 


+ 


- 


+ 


+ 


+ 


+ 


+ 



- NOT RECOVERED 
+ RECOVERED 



539 



CHEMILtJMINESCElilT BAGIEERIAL SMSOR 

]^ Judd R. Wilklns 
NASA Laaigley Research Center 



SUMMARY 




The ptirpose of the chemiltnnine scent hacterial sensor experiment during the 
90-day test was to determine (l) if the sensor co\ild rapidly detect gross con- 
tamination of recovered water and (2) the correlation "between sensor response 
and Tiahle couats. IThe sensor was tested 106 times. The results showed good 
correlation "between a strong sensor response and Tiahle coxmts on eight occa- 
sions. In 60 tests the sensor response was strongly positive, and the plate 
counts were either negative or below the level of sensor sensitivity or were not 
performed. Because the sensor responds to living or dead cells, these results 
suggest that the recovered water may have contained (l) dead "bacterial cells, 
(2) po3rphyrins leached from cells, or (3) substances unrelated to bacteria which 
triggered a positive response. With one exception, the correlation between a 
negative sensor response and plate coimts was good on 16 occasions. In 15 tests, 
quenching of the chemiluminescent reaction occurred. In general, the sensor 
was able to detect gross contamination rapidly, required minimxan crew participa- 
tion, and was easy to operate. However, further research is needed to determine 
the nature of those substances in the water which trigger a positive sensor 
response in the presence of negative or low viable counts; research is also 
needed to determine the nature of the quenching phenomenon. 

IMEODUCTION, 



During the 90-day test, the chemiluminescent method for rapidly detecting 
gross contamination of the potable and wash water recovery subsystems was eval- 
uated. The chemiluminescent reaction is that of alkaline luminol (5-amino- 
2,5-dll:iydro-l,il— phthalazinedione) with the cytochrome C portion of bacteria in 
which light is emitted. (See ref. 1.) USae amount of light emitted is a func- 
tion of the number of bacterial cells in the test sample with a sensor sensitiv- 
ity on the order of lo5 cells per milliliter. The purpose of the chemilumines- 
cent experiment during the 90-day test was to determine (l) if the sensor could 
detect gross contamination (greater thaja lo5 bacteria per milliliter) in the 
recovered water and (2) the degree of correlation between sensor response and 
viable bacterial counts. 



MATERIALS MD METHODS 



Located Inside the space-station simulator was a test chamber attached to 
a photomultiplier tube which was connected by means of bulkhead connectors to a 

5^1 



photometer and stripchart recorder located outside of the chataber. Operation of 
the chemiluminescent reaction experiment was performed inside the simulator by 
one of the cre-wmembers , who had "been trained prior to the 90-day test. All 
reagents and glassware were stored inside the chamber during the test. With the 
photometer and recorder wanned up, the test chamber was unscrewed from the 
adaptor which coupled it to the shutter. After the crewmemher had placed the 
luminol, sodixm perhorate, and sodium hydroxide reagents in the test chataber, it 
was reconnected to the adaptor. Ilhe shutter was opened, the recorder started, 
and 0.5 ml of the water sample was injected through the rubber septum. After 
the emitted light had been recorded, the shutter was closed and the recorder 
stopped. The test chamber was removed and cleaned in preparation for the next 
test. Total elapsed time for each test was about 5 minutes. Plate counts were 
performed by drawing 10 ml of recovered water through a Millipore field kit 
monitor, adding nutrient broth,, and incubating at 57° C for 48 hours. Counts 
were expressed as the number of bacterial colonies per milliliter and in those 
cases where overgro>rth occurred as "too numerous to coimt" (TNTC). 

DISCUSSIOE OF RESULTS 

During the 90-day test, ik- locations in the potable and wash water recoveiy 
subsystems were sampled for a total of 106 tests of the chemiluminescent detec- 
tor. A comparison of the chemiluminescent results with the HS-hovr viable counts 
obtained with the onboard Millipore field kits are presented in table I. For 
ease of handling, these data were divided into two parts: those which gave a 
positive sensor response greater than five UQlts on the photometer and those in 
which the readings were less than five, specifically, a negative response. 
Based on previous laboratory escperience with this reaction and equipment, the 
photometer had to register a reading of five or more before it was considered 
positive. In l^i- tests quenching of the reaction occurred. These res\ilts plus 
one case of failure to calibrate the photometer properly are not included in 
the following data analysis. 

Of the 68 onboard tests with a response equal to or greater than five, the 
correlation between the chemiltmine scent detector and the plate counts was good 
on only el^t occasions. As the onboard field-kit procedure did not permit a 
quantitative expression of the ntmiber of bacterial cells in these eight cases 
of contamination, the counts were recorded as too numerous to cotintj therefore, 
the water samples were indicated to be grossly contaminated. At the level of 
contamination which could be expressed in cells per milliliter, there were 10 
cases in which the counts averaged 50/ml? an<3. the sensor response was strongly 
positive with an average reading of 55 •? on the photometer. There were 53 cases 
in which the plate counts were negative and the sensor response was positive. 
There were I7 cases in which plate co^mts were not performed and the detector 
response was strongly positive. In reviewing the positive detector results, 
only a few preliminary statements can be made at this time. In only eight cases 
was thei'e good correlation between the plate count results and the detector 
response. As these plate counts were too niimerous to count, it can be ass'umed 
that the water samples were grossly contaminated. In ^5 of 68 positive detector 
responses, there does not appear to be any correlation between the detector and 



plate coxmts, in 10 cases the n-umber of iDacterial cells in the sanrples was "below 
the sensitivity of the detector, and in 33 cases the plate counts were negative. 
Ihere is, however, the possihility that a correlation does exist between the 
detector and plate counts for these ^5 cases even thoTjgh it is not apparent in 
the data presented in table I. It has been demonstrated by laboratory experi- 
ence that the chemiluminescent reaction works equally well on living as well as 
dead bacterial cells. Furthermore, it is also possible that the recovered water 
entering a storage tank or dispenser contained, viable bacterial cells which were 
killed by the heat (160° F) applied at these points. If this were the case, the 
low and negative plate count readings could contain dead bacterial cells, which 
would produce a positive detector response. In the 17 tests in which plate 
counts were not done it is inrpossible to determine if the positive responses 
were caused by living or dead cells or a mixture of these two. It i§ highly 
likely, however, that dead bacterial cells or soluble porphyrins derived frcm 
these cells were involved in these responses, and studies performed on water 
samples obtained after the 90-day test tend to stipport this concept.* Nine 
samples of water from different sources were analyzed for viable counts, total 
counts (living and dead cells), and soluble porphyrins. ' In seven cases it was 
impossible to differentiate between living and dead counts as quantitative counts 
were not perfoimed. In two cases the viable co-unts were negative, in a third 

case the count was 26 cells/mlj and the total counts were 1.0 X 10^, 2.4 x 10^^ 
and 4.9 X loVinl, respectively. Soluble porphyrin studies were performed on 
eight samples, and the signals were on the average 26 times greater than the 
distilled water control. lEhere is also the possibility that these "false posi- 
tive" responses could be caused by stflastances in the recovered water which were 
unrelated to bacterial cells but capable of triggering a response in the detec- 
tor. In either case more research is needed to resolve the nature of these false 
positive signals and the observed quenching phenomenon. 

In the 23 tests with negative detector responses, there was, in general, 
good agreement between the detector and the plate counts. In one case, the 
plate counts were too numerous to count, whereas the detector response was less 
than five. The reasons for this discrepancy are not readily apparent at this 
time. There appears to be good agreement between the low and negative plate 
counts and the detector, and in the three cases in which plate counts were not 
done, it is assumed that ira-ter samples did not contain living or dead bacterial 
cells . 



GOKCLnDBrG REMAEKS 

The purpose of the chemll-UDiiine scent bacterial sensor experiment dui-ing the 
90-day test was to determine (l) if the sensor could rapidly detect gross con- 
tamination of recovered water and (2) the correlation between sensor response 
and viable counts. The sensor was tested 106 times. The results showed good 
correlation between a strong sensor response and viable counts on eight occa- 
sions. In 6o tests the sensor response was strongly positive, and the plate 

^Personal communication from F. H. Seubold, Aerojet-General Corp., October, 
1970. 



5^5 



coomts were either negative or below the level of sensor sensitivity or were not 
performed. Because the sensor responds to living or dead cells, these results 
suggest that the recovered water may have contained (l) dead bacterial cells, 
(2) porphyrins leached from cells, or (5) substan&es unrelated to "bacteria which 
triggered a positive response. With one exception, the correlation between a 
negative sensor response and plate counts was good on 16 occasions. In 15 tests, 
quenching of the chemiluminescent reaction occurred. In general, the sensor 
was able to detect gross contamination rapidly, '^required minimum crew participa- 
tion, and was easy to operate. However, further research is needed to determine 
the nature of those substances in the water which trigger a jKDsitive sensor 
response in the presence of negative or low viable counts; research is also 
needed to determine the nature of the quenching phenomenon. 



REEEREmCE 



Oleniacz, Walter S.j Pisano, Michael A.j Rosenfeld, Martin H.j and Elgart, 
Robert L.: Chemiluminescent Method for Detecting Microorganisms in Water. 
Environ. Sci. Technol., vol. 2, no, 11, Nov. I968, pp. 1050-1053. 



'^hh 



TABLE I 

COMPARISON OF CHEMILUMINESCENT BACTERIAL SENSOR READING 

WITH FIELD KIT PLATE COUNTS DURING THE 90-DAY TEST 





SENSOR READING POSITIVE (^5) 
68 OF 91 TESTS (75%) 


SENSOR READING NEGATIVE «5) 
23 OF 91 TESTS (25%) 




PLATE COUNT* 


PLATE COUNT* 




TNTC** 


PER ml, 
AV.50/ml 


NEG. 


NOT 
DONE 


TNTC** 


PER ml, 
AV.112/ml 


NEG. 


NOT 
DONE 


NUMBER OF 
TESTS 


8 


10 


33 


17 


1 


3 


16 


3 


PERCENT 


12 


15 


48 


25 


4 


13 


70 


13 


AVERAGE 
SENSOR READING 


29.6 


35.7 


20.3 


7Z1 


1.0 


2.8 


2.3 


1.3 


RANGE OF 
SENSOR READING 


6.5-73.5 


5-250 


7-60 


6-515 




L5-3.0 


a5-4.0 


a5-2.0 



♦AFTER 48 HOURS INCUBATION AT 37° C. 
**T00 NUMEROUS TO COUNT 



5it5 



RADIATION SAFETY REPORT 
ON THE USE OF 238pji02 AS A HEAT SOURCE 

By A. A. Kelton, Ph. D. 

McDonnell Douglas Astronautics Company 

SUMMARY 

238 
Heat from five capsules containing PUO2 in the form of microspheres 

was used to pbwer a water recovery subsystem in the 90-day manned test of a 

regenerative life support system in a Space Station Simulator (SSS). Despite 

76 manipulations of capsules at a whole-body dose rate of 25 mrem/hr and the 

existence of a radiation area in a regularly traversed area of the SSS, the 

average in,tegral exposure for 90 days of confinement was only about 100 mrem, 

less than 10 percent of the normally allowed dose. Simple, manageable 

handling tools and straightforward procedures prevented any thermal injuries 

and detet^red excessive exposure of the extremities to ionizing radiation. No 

discernible damage was sustained by any of the capsules^and no release of 

radioactive contamination could be detected. Several improvements in devices 

and procedures for the radiological safety of radioisotope power applications 

in manned spacecraft were identified as a direct result of studies in the SSS. 

These studies indicate that current tendencies toward excessive protective 

measures maybe unnecessarily impeding application of thermal power from 

plutonium-238 to such space systems as Skylab and Space Station. 

INTRODUCTION 

One of the record events accomplished during the 90-day test of an SSS 
was the use of radioisotope heat to power a water recovery subsystem for 
four crewmen within a sealed environment. This part of the regenerative life 
support system consisted of a vacuum distillation -vapor filtration (VD-VF) 
unit heated by 340 watts from five encapsulated radioisotope heat sources. 
These were fueled by about 10, 000 curies of '^3°Pu02 in the form of 
microspheres. 

A major obstacle to general acceptance of radioisotope power as a 
simple and dependable source of thermal energy within manned spacecraft has 
been uncertainty about onboard radiological safety problems, such as shielding, 
placement of capsules, and radiation exposure of the crew during handling of 
the capsules and continuous work within a radiation environment. Since ther- 
mal energy can constitute over one half of the basic power requirements of a 
manned spacecraft (e.g., Skylab) the use of radioisotope heat could signifi- 
cantly decrease electrical power requirements and/or increase mission 
capability. The 90-day manned test provided a unique opportunity to safely 
evaluate radiological hazards under simulated conditions. 



5^7 



The radiological safety program for the 90-day test dealt with two 
distinct hazards. The most prominent hazard consisted of direct exposure of 
personnel to ionizing radiations emanating from the capsules. The second 
hazard derived from the very remote possibility that a capsule might 
accidentally leak radioactive contamination. Trained personnel and special 
equipment, facilities, and procedures were employed to protect the health of 
the crewmen and to evaluate the significance of these radiological hazards so 
that similar radioisotope -fueled devices might be safely and confidently 
employed in a future Skylab or Space Station. 

RESULTS 



Evaluation of External Radiation Hazards 

The external hazard posed by the radioisotope heat source capsules 
consisted of neutrons and gamma radiations. Neutrons, the most ^prevalent 
and hazardous radiation, emanated from spontaneous fission of ^^°Pu and 
(a, n) reactions within the '^ °Pu02. Gamma radiations resulted from the 
radioactive decay of daughter products and impurities and constituted about 
10 percent of the dose. A 73-watt capsule produced a dose rate slightly 
greater tjian 5 mrem/hr at 1 meter and about 25 mrem/hr to the eyes and 
whole body at convenient handling distances. Such dose rates necessitated 
shielding ^he VD-VF unit, consideration of the location of the VD-VF unit a'nd 
storage container (chill box) within the SSS, and thorough analysis of handling 
operations. 

The interior layout of the SSS with respect to the radiation areas is 
shown in fig. 1. As indicated, the VD-VF unit was located in the equipment 
and storage rqoTti. When the VD-VF unit was not in operation, the capsules 
were stored in water contained in a chill box located across the aisle from the 
VD-VF unit. The water was used to cool and shield the capsules. 

A movable, U-shaped tank containing water was constructed to shadow- 
shield the VD-VF unit. Stationary water tanks above, below, and behind the 
unit were also a part of the shadow shield. A sketch of the shielding arrange- 
ment is shown in fig. 2. Calculations indicated that at least a 10-in. thickness 
of water in the shield would be required for uncontrolled access to the area 
(8-hour working day). Due to the volume occupied by the VD-VF unit and its 
thermal insulation, the mass and dimensions of such a shield would have been 
incompatible with easy access to the VD-VF unit, space available in the 
equipment and storage room, the actual time spent by the crew in the vicinity 
of the unit, and the general objectives of the program. As a compromise, 
shielding guidelines were established to prevent exposure of any major portion 
of the body to a dose rate in excess of 5 mrem/hr for the majority of activities 
and normal traffic within the equipment, and storage room. Shielding was such 
that during normal operations of the VD-VF unit no area was accessible to 
personnel that would result in exposure of a major portion of the body to a 
dose rate in excess of 100 mrem/hr. When the layout of the equipment and 
storage room and the schedule of crew activities were examined, the usual 
activities and traffic were at distances greater than 1 meter from the outer 

5W 



surface of the shield. Calculations for this condition indicated that a 4-in. 
thickness of water plus the water always present in the VD-VF unit would 
shield to a dose rate of about 25 mrem/hr at the surface of the shield and 
2. 8 mrem/hr at 1 meter from the surface. 

Before the shield was constructed, the conditions of exposure were 
analyzed to assure that no crewman would be knowingly exposed to an integral 
dose that would exceed the allowances given in the radiation protection guide 
(table 1). 

The dose rates were calculated for various locations within the Space 
Station Simulator. Using these data, the maximum integral dose to a crewman 
was tabulated as shown in table 2 according to the schedule of crew activities 
and the m.aximura dose rate for the location of that activity in the SSS. Fromi 

table 2, the integral dose for 90 <3ays was expected to be less than the gen- 
erally allowed dose 1.25 rem and well within the 3 ^em that could be permitted 
for 3 months of radiation work. The actxial dose rates were measured with 
neutron and gamma sxnrvej meters before the beginning of the '^O-daj test. 
These dose rates are indicated in figures 2 and 3 and essentially agreed with 
the calciolated dose rates. 

Personnel dosimetry during the 5-day checkout and the 90-day test 
consisted of film badges and pocket dosimeters. The film badges were the 
legal record of the radiation exposure of the crewmen. Each crewman wore 
two film badges and two pocket dosimeters. One film badge contained both 
neutron and gamma- sensitive filins. During the 90-day test, a supply of film 
packets was stored in the cabinet in the living quarters most distant from the 
radiation area. Each week, the crew changed film packets in these badges and 
sent the exposed packets, plus a control packet, out of the SSS via the weekly 
pass-out of samples. The other film badge contained only a gamma- sensitive 
film and was retained for the full 90 days. The film packets were specially 
supplied, developed, and evaluated for the recorded dose by the Office of 
Environmental Health at the University of California at Los Angeles. Each 
crewman was also issued a set of direct- reading pocket dosimeters, one 
sensitive to gamma and the other sensitive to neutron and gamma radiation. 
The total accumulated dose indicated on each dosimeter was recorded daily. 
The pocket dosimeters were only used to indicate any excessive daily exposure. 
At low doses (<Z divisions/200 scale divisions), these dosiraeters were prone 
to artifact and large inaccuracies in use and interpretation. 

The film badge results are shown in table 3. Three of the four crewmen 
received total doses lower than permitted for the general population. The 
fourth crewman received only 25 percent of the maximum expected dose, 
14 percent of the generally allowed dose, and about 6 percent of the maximum 
permissible dose for 13 weeks. The low levels of gamma radiation were not 
detectable on either the weekly or 90-day film packets. The pocket dosimeter 
readings were considered to be unreliable due mostly to large errors in 
interpreting the readings and lack of agreement between the neutron and gamma 
dosimeters of each set. 



In general, both the film badge results and the pocket dosimeters 
indicated that handling of the capsules constituted the greatest source of 



5^9 



radiation exposure. The record of capsule handling is shown in table 4. The 
capsules were exchanged between the VD-VF unit and the chill box on 
14 occasions which resulted in 76 manipulations of individual capsules. By- 
examining the frequency that each crewman handled the capsules and the 
differences in their recorded radiation doses, the average dose to a crewman 
or a handling operation can be estimated. Figure 4 illustrates the technique 
of handling and the radiation environment surrounding the capsule. The 
capsule was held in about the same geometry throughout each transfer, so 
that the average dose can be approximated at 1 to 3 mrem. The average 
transfer time including a smear test was estimated at 2 to 6 minutes. 

Evaluation of Radioactive Contamination Hazards 

Problems of control of radioactive contamination were not anticipated. 
First, the capsules were designed and tested to prevent release of any- 
radioactive materials for all credible accidents during shipment of the 
capsules or testing of the VD-VF unit. Second, special procedures and 
equipment were used to prevent credible accidents. Third, the chemical and 
physical form of the ^^°Pu02 microspheres minimized the danger to health 
and property from contamination in the unlikely event of capsule leakage or 
rupture. Nevertheless, a rigorous program of control was conducted in the 
event of accidental release of radioactive material from the capsules. The 
program emphasized the detection and containnaent of radioactivity and emer- 
gency procedures to minimize any contamination of personnel or property. 

A preliminary accident analysis gave the following results. The total 
mass of plutonium-238 was less than 10 percent of the minimum critical mass 
reflects. Further, the storage and utilization of the capsules in water 
lessened the potential for criticality, which was clearly impossible. The 
worst credible accident would have occurred if the double encapsulation of a 
heat source were ruptured and the contents spilled onto the floor of the 
closed SSS. Approximations indicated that if an air monitor warning were 
given within 30 sec, the crew could probably have es.caped from the SSS 
without overexposure to °Pu. The regulations which limiit internal exposure 
to '^^°Pu02 are shown in table 5. The critical organ was considered to be the 
lung and only the limits for the insoluble form are relevant. Procedures were 
adopted to prevent such an accident or, indeed, any damage to the capsules. 

A more credible accident would have been the leakage of radioactivity 
from a capsule resulting from mechanical or chemical damage or manufac- 
turing defect. The leakage would have been augmented by helium buildup in 
the capsule and might have been a slow seepage or a rapid leak (puff) with 
the helium expanding and diffusing through the microsphere fuel. No data 
are available for a reliable evaluation of the consequences of capsule leakage. 
Using several approximations, a slow leak was not expected to yield a maxi- 
mum permissible concentration (MPC) of 10" ■'^■'^ |jiCi/cm-^ for continuous 
exposure of the lung. However, a puff release might produce a concentration 
of ^-'°Pu02 in air that would exceed acceptable limits by factors as large as 
10^ to 10^. Such concentrations could result in a maximum permissible lung 
burden (MPLB) for a crewnaan within 1 to 10 hours. Another credible, but 

550 



unlikely, accident could have resulted from overheating of a capsule. If the 
capsule were thermally insulated until its temperature exceeded ~2, 000°F or 
~1300°K, the capsule naight rupture because of internal helium pressure 
augmented by other mechanical stresses. Calculations showed that at such 
temperatures the volatilization of ^^°P\i02 could release radioactivity at the 
rate of ~13 |j.Ci/hr. Such a release rate within the SSS would exceed the MPC 
for 238pu within 1 minute and could result in a MPLB within about 1 hour. 
However, in view of the many precautions instituted, no conceivable accident 
could have resulted in a capsule overheating or even reaching its design 
operating temperature. 

The procedures for detecting any release of radioactivity included air 
monitoring, smear analysis, radiation survey, and water analysis. The air 
in the vicinity of the capsules was continuously monitored for a-emitting 
contamination by an air monitor equipped with an audible and visual alarm. 
During every handling operation, the entire surface of each capsule was wiped 
with a dry cloth. All smears were checked for a-emitting contamination with 
an a- survey meter and occasionally checked with an isotope analysis unit. 
Handling devices, personnel, clothing, and any surfaces coming in contact 
with the capsules were surveyed for a-emitting contamination. Prior to 
human consumption, samples of reclaimed water from the VD-VF unit were 
monitored for radioactive contamination by survey of the dried samples and 
analysis in the isotope analysis unit. 

The air monitor filter was changed daily>and the air monitor was checked 
for performance and calibrated with a ^-^"Pu a- standard. The a- standard was 
also used to calibrate the a- survey meter before use and the isotope analysis 
unit. Emergency and contingency procedures were adopted and were to be 
instituted whenever predetermined levels of radioactivity could be detected in 
the air or water or by a smear test. 

The results of continuous air monitoring are shown in figures 5 and 6. 
The daily reading of the air monitor ratemeter decreased rapidly during the 
first few days corresponding to the rapid decay of radon after the SSS was 
closed. Based upon the MPC of 238pu in air for continuous exposure and the 
sampling rate and counting efficiency for the air monitor, contingency 
conditions were established for an alarm at 300 cpm. Emergency procedures 
were required to prevent inhalation of an MPLB when a time of less than 
5 minutes elapsed between an alarm at 300 cpm and an alarm at 1, 000 cpm. 
The air monitor failed on several occasions. Two false air monitor alarms 
occurred, once during the 5-day trial and once during the 90-day test. In both 
cases the crew established within 0. 5 to 1 minute that the alarm did not result 
from radioactivity but instrument malfunction. A short circuit in the 
ratemeter caused the first alarm, while a noisy photomultiplier tube caused 
the second alarm. Batteries in the scintillation probe had to be replaced 
twice during the 90 -day test. Finally, the constant-flow air pump failed on 
the 88th day and was replaced with an air pump normally used for bacteriolog- 
ical sampling. Measurement for any radioactivity on the daily air filters was 
also performed with the isotope analysis unit. From fig. 6, the early results 
were unusually variable considering the stability of the instrument. Further, 
the value of a particular measurement was found to decrease as the time after 
removal of the filter increased. Preliminary tests by the crew suggested that 

551 



the aberrant measurements were caused by a static charge on the filter which 
neutralized the charge on the quartz fiber electroscope (isotope analysis unit). 
This conclusion was verified by experiments following the 90-day test. The 
difficulty was corrected on day 57 by allowing an extra day to elapse before 
measurement. Using the isotope analysis unit, the contingency level for air 
filters corresponded to the time for the quartz fiber to move 20 scale divisions 
in less than 45 minutes or at a rate of 27 units/hr. An emergency condition 
prevailed when a deflection of 20 scale divisions occurred in less than 50 sec. 

The results of surveys for radioactive contamination are shown in 
table 4. No a- emitting contamination could be detected above the background 
radiation levels normally indicated by the a- survey meter. One false indica- 
tion of radioactivity occurred following a smear test on capsule BT-38. This 
smear was immediately checked on the air-monitor probe and with the isotope 
analysis unit. Both revealed no radioactivity. The false alarm was traced to 
a noisy photomultiplier tube which was replaced. 

Measurements of water samples and some smear samples with the 
isotope analysis unit are shown in fig. 7. None of these measurements were 
significantly different than background measurements. The contingency levels 
for gross pY activity were a rate of > 10 div/hr for a smear sample and 
2:5 div/hr for a dried 20-ml water sample. A MPC of ^^°Pu in the drinking 
water would have given a deflection rate of about 300 div/hr for a dried 20-ml 
sample. An emergency level corresponded to a deflection of 20 scale 
divisions in less than 6 minutes for a smear sample and less than 20 sec for 
a water sample contaminated with ^-^"Pu. 

DISCUSSION 



The 90-day manned test of a Space Station Siraulator has resulted in data 
and assessments that will be useful in the realistic evaluation of radiological 
safety problems arising from the potential use of plutonium-238 heat sources 
in future life support systems of manned spacecraft. In particular, the 
questions of difficulties and hazards in handling of the heat source capsules and 
the dose resulting from crew activities in the presence of an open radiation 
area can now be addressed with the perspective of experience. 

Some of the results suggest definite answers to such questions. Thus, 
the heat source capsules were handled in 76 separate manipulations without 
incident or difficulty. Simple and manageable handling tools and practical 
procedures prevented any thermal injuries and deter'red excessive exposure of 
the extremities to ionizing radiation. No discernible damage was sustained 
by any of the capsules and no release of radioactive contamination could be 
detected. Despite the existence of an open radiation area in a regularly 
traversed section of the SSS, the average exposure of the crewmen was less 
than 10 percent of the normally allowable dose, within the level permitted for 
the general population, and only 13, percent of the maximum predicted dose. 
Such observations should counteract prevalent tendencies to overshield, over- 
complicate, and overprice in those space programs that seek to employ the 
advantages of radioisotope power. 

552 



Perhaps the most useful result of this test will be the development of a 
methodology to more accurately predict the dose to the crew of a Skylab or 
Space Station as a result of the use of radioisotope heat in life support sub- 
systems. Personnel dosimetry indicated that total dose of the test was much 
less than that estimated. The overestimate was caused by the inclusion of 
safety factors in the calculations of dose from handling, shielding, and the 
distance and time associated with each scheduled crew activity. Detailed data 
are now available regarding actual crew movements within the Space Station 
Simulator. The crew work schedule was planned in extreme detail and 
meticulously monitored throughout the test. The location of each crewman 
was determined every 2-1/2 minutes during substantial portions of the test. 
Following computer reduction of these data, summaries of the locations and 
durations of the tasks can be compared with the planned schedule for the crew. 
Once integrated with the other test results, this information will yield more 
realistic safety factors for future use in optimizing the shielding weight and 
the location of radioisotope sources in relation to expected crew activities. 

The 90 -day test also indicated that a definite spacecraft requirement 
exists for the development of instruments, devices, and procedures to detect 
and contain radioactivity. Although extreinely remote, the possibility of a 
radioactive contamination hazard must be neutralized in the closed environ- 
ment of a manned spacecraft. Approximate calculations indicated that damage 
resulting in leakage from one or more of the capsules or overheating with 
capsule rupture could release airborne radioactivity that would rapidly exceed 
the maximum permissible concentration in air and result in a maximum 
permissible lung burden within minutes. However, the inagnitude and 
characteristics of any release of radioactivity would need to be experimentally 
determined to realistically design for the hazard. Nevertheless, design 
requirements, such as the inclusion of a small, lightweight containment 
vessel with air mionitoring, or a heat pipe to remove excessive heat, could be 
adopted that would greatly reduce the significance and hazards of these remote 
possibilities and provide the opportunity for remedial action. In particular, 
the 90 -day test revealed the need for several improvemients in radioactivity 
monitoring instruments. Some of the features that should be included in the 
design of the air raonitor and survey meter are 

A. An electronic means of discriminating between an alarm caused by 
instrument malfunction and one resulting from radioactivity. 

B. Warning indicators of radioactivity level, radioactivity release rate 
(air monit. r), and instrument failure. 

C. Built-in radioactive calibration sources, electronic calibration, and 
elective indications of critical voltages. 

D. Interchangeable ratemeters, detector assemblies, and some 
electronic components. 

Although the development and test of such equipment and methods are an 
essential adjunct to use of radioisotope power, they involve existing capability 
and technology and should require only a minor effort and expense. Most of 

555 



the design improvements suggested in this report were identified as a direct 
result of the monitoring experience in the Space Station Simulator. 

An important contribution of the 90-day test was proof of the value of 
simulated testing of procedures and instrumentation designed for radiological 
safety in manned space systems. Thus, before final acceptance of instrument 
designs and procedural concepts for radiological safety in a future Skylab or 
Space Station, prototypes should be evaluated in a manned test of a Space 
Station Simulator. This should include an evaluation of the methodology used 
to predict crew dose and determine shielding based on location of the radio- 
isotope heat sources and crew activities. The handling characteristics of 
flight-rated radioisotope heat sources and the long-term operating charac- 
teristics of these sources in life support subsystems should be determined. 
The performance of space flight prototypes of the air monitor, survey meter, 
and personnel dosimetry should be substantiated. The procedures, instrumen- 
tation and crew performance should be further evaluated under the duress of 
simulated credible accidents. The experience gained by such testing is certain 
to establish confidence and perspective not attainable by speculation. 

238 
In conclusion, the use of Pu02 fueled heat sources in a 90-day manned test 

of a life support system in the Space Station Simulator represented a significant 

advancement in the acceptability of radioisotope power sources for use within 

manned space stations. 



REFERENCES 



1. Abraliamson, S. Gj Carfango^ D. G.j and KoKenge^ B. R. j compilers: 

Plutonimi-238 Isotopic Fuel Form Data Sheets. MEM 1^6k-, Monsanto Research 
Corp., 1968. 

2. Anon.: Report of Committee II on Permissible Dose for Internal Radiation. 

ICRP Publ. 2, Pergamon Press, Inc., 1959. 



55^ 



TABLE 1.- FEDERAL RADIATION COUNCIL RADIATION PROTECTION GUIDE* 



TYPE OF EXPOSURE 


CONDITION 


DOSE (REM) 


RADIATION WORKER: 






(A) WHOLE BODY. HEAD AND TRUNK, ACTIVE 
BLOOD-FORMING ORGANS, GONADS OR 
LENS OF EYE 


ACCUMULATED DOSE 
13 WEEKS 


5 TIMES THE NUMBER OF 
YEARS BEYOND AGE 18 
3 


(B) SKIN OF WHOLE BODY AND THYROID 


YEAR 
13 WEEKS 


30 
10 


(Q HANDS AND FOREARMS, FEET AND ANKLES 


YEAR 
13 WEEKS 


75 
25 


(D) BONE 

(D OTHER ORGANS 


BODY BURDEN 

YEAR 
13 WEEKS 


0.1 MICROGRAM OF 
RADIUM-226 0RITS 
BIOLOGICAL EQUIVALENT 

15 
5 


POPULATION: 






(A) INDIVIDUAL 


YEAR 


0.5 (WHOLE BODY) 


(B) AVERAGE 


30 YEAR 


5 (GONADS) 


'FROM FEDERAL REGISTER, 18 MAY 1960 







TABLE 2.- MAXIMUM INTEGRAL DOSE FOR THE 90-DAY TEST 





MAXIMUM INTEGRAL 




MAXIMUM INTEGRAL 


CREWMAN'S ACTIVITY 


DOSE(MREM)* 


CREWMAN'S ACTIVITY 


DOSE (MREM)* 


LRC TESTER 


9.4 


MAINTENANCE 


26.5 


EATING , 


24.0 


LAUNDRY 


3.8 


SIFFPING 


72.0 


CABIN CLEANING 


8.0 


EXERCISE 


57.0 


LSS MONITORING 


2.2 


RECREATION 


178.0 


PASS-OUT 


2.0 


BODY HYGIENE 


90.0 


QUESTIONNAIRE 


0.8 


WASTE MANAGEMENT 


45.0 


MICROBIOLOGICAL 


1.5 


COMMUNICATIONS 


55.0 


WASTE WATER FILTER 




PHOTOGRAPHY 


8,9 


CHANGE 


1.5 


MEDICAL DATA 


4.4 


PSYCHIATRIC INTERVIEW 


0.2 


SAMPLE COLLECTION 


16.0 


SERUM SAMPl£ 


0.6 


MICROBIAL CULTURE 


8.7 


PHARYNGEAL 


0.3 


DATA MANAGEMENT 


18.0 


UNSCHEDULED ACTIVITIES 


34.0 


MEDICAL INTERVIEW 


16.5 


VD-VF CHANGEOVER 


120.0 






TOTAL 


804.3 


INTEGRAL DOSE FOR ALL ACTIVITIES DURING THE 90- 


DAY TEST IS APPROXIMATELY 


800 MREM 



•CALCULATED FROM PRELIMINARY ONBOARD TIME DEMANDS WITH THE ASSUMPTION 
OF A FOUR-INCH SHIELD OF WATER AROUND THE VD-VF UNIT. 



555 



to 
o 



< 



m 
u 



lo &000000 
I (M r- I- f- «- 



O Q O O O O O 

n <^ I CM 



CSI 



^o oooooooooooool o 



o 

(M 



o 

CO 



a: ^ 



o 
o 

< 

QQ 





pj 




, 




o 


2 


z 


UJ 


z 


UJ 


< 


S 


% 


UJ 


UJ 


cc 


oc 


Z 


o 







z 
o 
a. 

V) 

=^ 

UJ K- 



I CM 



£| 



o o oo o o o o o oo ooo I o 



o 

I— 
M 



o 



>- 






CO 

o 
o 



o 



rr> 



QQ 

< 



UJ 








o 




o 




-1 
< 


JM 


3 


d 


Q 


z 






> 


z 


O 

z 


< 




m 




a. 




u 



III ■ 



o o o o o o o o o o o o o o o 



g 



s 



zi^S^uj 

±UJ H- m UJ ^UJ 

Si lu X ocOh 

--. H M C < X 9 

fu.g^|s5 

•^ ^ H S. f q _. is 

"•^ wC SuJoc 




CO 



UJ 



c|o oooggogoooooo o 



^* 



ooooooooooooo 



CO 

coo 

is 

UJ O O 






w 



u 

<5o£ 
oujo tr 



«H S UJ 
2i£ UJ X£|3 

u. c/) ^m 

< Qouj" 
!: Oujcci-' 

S? CCX3W 

t ''-UJ?'" 

2 ui zfi < 

ISgcozg 



m UJ — 



uI 

Sa^uj 

"uj 

CO 



UJ 

I- 

< 
o 



r-CMCn<«'lf)(OC>COa>Or-Ci(m 



5 <uj 

O o^ 

I- f-* 

« UJ* 



* 

^= 

Q uj' 
UI tn 

UJ 

oc 
cc 
o 
u 



UJ 

Pz J z ^ UJ S<I 
fe«- ^ CO X i-=t- 

£p^zO-^g 
rf CO cc CO O -J h-3 > 
H-UJI-jCC cO|-°t 

jaxz<5»5i-5 

l-«»o^" UJ CO q2 5 

ZSSCCO 2 uiujZ§ 




UJHOQq** 

IujS<OC ^• 

2Ei£S ^^ 

jJ-ZH"- g 

« * z 



556 



CO 



a: 

ZD 
CO 

< 



Q 


^ 


2 


< 


<• 


1— 


T 


^ 




o 


UU 


c> 


1 




ZD 


UJ 


CO 


> 


a. 




< 


1— 

o 
< 


LL. 


o 


O 






o 


Q 


< 


on 


c^ 


O 




C^ 


Qi. 


uu 


O 


q:: 


u_ 


1 

• 




UJ 




1 




QQ 




< 

























CO 






















2 


cc 






Z 














Ij _ 
0- 


UJ 





















0} u. 


u. 
(/} 

z 
< 






(I 















ui:> 






3 








Ul 

oc 






£ i§ 


oc 
oc 

2 




U. 


S 
U 


u. 




> 


3 
u. S 


U. 


^ 
^ 


2 ^^ 

U. guL U.O 

t^ z Q SP 

u. p u. »- 1: 
5 <3 




O 





Q 


< 


< 


z 





< 


z 




> 
u. 


> 

u. 


§- 


5 


>o 

U. [I 

5 


> 

u. 


§ 


M 




O 


Ij 





"0 


U 





u 


^ 




a. 


a 


a. 


q Q. 


Q 


0. N 


Q. 





0. N Ol = X 


LU 




3 


3 


UJ 3 


UJ 


3 -. 


3 


UJ 


3 '^ 3 2 w 


CC 




1- 


UJ 


H 


s •- 





F- d 


H 





H d »- 1 J 






cc 
< 


Z 


CC 
< 


85 


8 


5 «= 

< Ul 


cc 
< 


1 


OC oc OC 3 <£ 

< »" < gz 






fe 


OC 

3 


l^ 


uffe 


-1 
u. 


\h^ 


^ 


-J 
u. 


to to lo <u. 








X 




X 


X 


X 




X 


X X 


































• 


OQ 




OQ 


OQ 


* OQ 




CO 


OQ 00 


Q 


? 


u. 


_t 


u. 


-1 u. 


-1 


U- _1 


u. 


_i 


U> -1 U- -1 


> 


-J 


:> 


=i^ 


J 


> -1 


> 


-1 


^ ■±>, :± 


ffioc 




O X 


Q 


I Q 


X 


Q X 





I 


Q X Q X 


jOC 




>o>o>o>o> 





> > 


PSU 
ISFE 
























X 




X 


X 




X 


X 




X X 


<5 


S 


o 




















§ § 


"^ 


o 


flQ 




CQ 


OQ 




OQ 


OQ 




cc 


cc 


_l 


UL 


J 


U. _i 


u. 


-J u. 


-J 


u. 


-J u. ^ u. 


h- 


u. 


d^ 


^ 


=? d 


>, 


zi >. 


^ 


:> 


^>. i±'^ 






3:9 


X 


QI 


Q 


X Q 


X 


a 


I Q X Q 






o> 


> > 


> 


u 


> > > 




^ 












* 
* 

S 
OC 










te 














< 





0000 


Z 


OQ 


^ ^ 


^ 


^ ^ 


^ 


d ^ 


^ 


X 


X X X X 


o 




GO 


OQ 


OQ 


OQ OQ 


OQ 


< OQ 


OQ 


OQ 


00 OQ OQ 00 


!5 






















ZUJ 


N 


(900C9(300<9OO(9C900 


11 -J 
S3 


^ 


^ ^ 


^ ^ ^ 


•:£. 


^ ^ 


^ 


X 


X X X X 


CO OQ 


OQ 


OQ OQ 


OQ 


OQ OQ 


OQ 


00 


OQ OQ 00 CO 


^ a. 






















Z< 






















ING CO 
EACHC 




CD 


C7 











0000 


t 


^ ^ 


^ 


'id, ^ 


^ 


^.^ 


^ 


X 


X X X X 


OQ OQ 


OQ 


OQ OQ 


OQ 


OQ OQ 


OQ 


OQ 


00 00 OQ 00 


Pi 

lUu. 

< 


in 


00 











000 





0000 


^ 


^ ^ 


^ 


^ >^ 


^ 


^ ^ 


^ 


X 


X X X X 


C3 CO 


OQ 


OQ OQ 


OQ 


OQ OQ 


00 


00 


00 CO 00 OQ 


X 
a. 


2 





000 


000000000 


< 


^ 


^S 


V 


^ ^ 


^ 


^ b^ 


>[f 


X 


X X X X 


^*» 


GO 


OQ 


OQ 


00 


CO oa 


CQ 


OQ OQ 


OQ 


OQ 


00 00 00 OQ 




111 


^ 






m 


« 


(O »- 


^ 


l»« 


— ^* ^ 




«— 


9 


9 


i" ^ 


r- 


T ^V 


(Vi 


*? T T T 




^ 


6 


ri 


ri 


i4 ri 


ii 


Ps p* 


l«* 


fi 


00 09 00 O) 



i=S 



CO 



UJ 



UJ 



UJ 



5OE: 



OS ii 






Z£ 



O 
X 
GO 



557 



< E 









UJ m oc 

I- tc 
o — 

UJ 



m n m oi 
6 6 66 6 






ij >« X S 



^ r- r-»- I— 

in M mm « 



3 
QL 
OO 
CO 
CM 



CO 

ULi 

o 



o 
cc 

Ob 



— lu ? ;^ 



< 

UJ 1—4 ' 
_JI 

— i <D 

— CD 

o ^ 



QQ 
O 

O 
< 

I 



lU 



K ^ 



ui 

oc 






«M CM 1- *- 

6 6 66 6 



<S 



X 

00 



X 
CM 



d^ 






r^ r- 1— »- r- 
XXX 
(O 0000 



QQ 

< 



_ UJ 

o z 
•^ - oc 

UJ 



5° 

o 



UJ 
DC 



d CM fO ' w 

d d d ! c) 



> 

a 



UJ 



S5 



>-2.' 
oc w— — 



(Ouj 

!2^ 



o = 



UJ 

Q 

J u.^ 

< 
oc 



8 



8 



i 



f§- 



UJ 






558 




CM 



OO 



I' 




NO 









LU 

o 

< 


< 




:i^: 




• 






P= 




o 

1— 

OO 




8 

.J 




u 

o 






.^^ 


lD 


.x^ 


,j^_ 






2 




o 

< 

1/1 


UJ 

O 

< 


UJ 

o 


PARATIO 
CREATIO 


< 

o 
o 


UJ 


S 

•iH 

CO 

§ 




— « 


< 


_J 


tfiif 


UJ 


Qi: 


> 


c^ 




jj 

— 

z 

o 


l±! 

CO 

< 


< 
o 

CO 

a: 
1 1 1 


O 

s 




:i^ 3 00 

§ Q^ iJ? 


5 

o 
o 

5 


<D 




o 


S: 


Q. 


u. 


o 


oQ < a. 


< 


CO 






• 




• 








'S 




o* 


o 




f— 1 


cvj 


pr» ^ tn 


NO 










00 
1— 


r- * 


1— < 


1.^ 1.^ r-i 


1—4 


1 
o 




UJ 




< 
Q- 






E o 




T3 




< 

g 

CO 




ILJJ 






S < 




CD 






Of: 

< 

CO 


F= 




EQUIP 
/STOR 




1— 1 

a 




v5 




u3 
O 


t/1 




a: . < 




O) 




UJ 


§ 

CO 

d 


< 


< 


OAAETER 

SUPPO 

VF UNIT 

OARD L 




• 




X 


^ 


< 


S 


o 


UJ 1 QQ 

ii o z 








UJ O 


^ 


o 


UJ 


-1 > O 






o 


















.11 


t— 4 


Csl 


t*\ 


^* 


• 


• • • 
vO t^ OO 






o 


















a 



















559 



UPPER RECEPTACLE 
FOR 48-W CAPSULE 



SIN. - 
7.0MREM;HRn 




ACCESS TO FOUR 
RADIOISOTOPE 
HEAT-SOURCE 
CAPSULES 



Figure 2.- Radiation survey near VD-VF 
unit with retracted shield. 




0.5MREM/HRY 



HOLDER FOR 

HEAT-SOURCE 

CAPSULES 



OUTSIDE SPACE STATION 
SIMULATOR 2.4MREM/HRn 
1.0MREM/HRY) 



Figure 3.- Radiation survey near isotope storage 
container in SSS (chill box). 



560 




1 1 1 


o^ 


r 


(X. 


X 


o^ 


s 




X 


tr\ 


LU 


s 


«M 


O^ 


LU 




^ 


0^ 




s 


S 
» 



0) 

I— I 

ca 

§- 
o 

00 
CO 
CSJ 



faC 
C! 

•r-l 
I— I 

t3 

C! 
(SJ 
Xi 

bC 

•i-t 

o 

.1-1 

•r-l 
-% 

u 
bD 

•1-4 



o 



o 
a 

W 



$-1 
•i-i 

Pi4 



^ »^ N « <* 

X 



561 



30 



25 



20 



il5 



10 























1 








11 " 


1 


/i0^^'[ V 


(D 


V. 


11.11 


^srfiiSsifiisa:',', 




,,,,v 


^J?f 


WfB 


^ iV 1 1 1 


5 10 15 20 25 
JUNE 


5 10 15 20 25 
JULY 


5 10 15 20 25 
AUGUST 


5 10 15 20 25 
SEPTEMBER 



▼ FALSE AIR MONITOR ALARM, PROBE SWITCHED 

V AIR MONITOR MALFUNCTION, BATTERIES REPLACED 

© AIR MONITOR PUMP FAILURE. INSTALLED BACTERiaOGY AIR PUMP 

Figure 5.- Measurement of radioactivity on daily filters from the 
air monitor (daily reading of air-monitor ratemeter). 



12 3 











■■-. 




li 








l^ 




a h h 


I 




V 

* 


mM 


h 






U^ V r jlj 


'* vU'^vA/v.^ 


<v,*>/v 


1 1 1 1 1 


1 1 1 1 1 


1 1 1 1 1 


1 1 1 1 1 


5 10 15 2 
JUNE 


25 


5 10 15 20 25 
JULY 


5 10 15 20 25 
AUGUST 


5 10 15 20 25 
SEPTEMBER 



♦VARIATIONS IN MEASUREMENT AT EARLY AND LATE Tl WES AFTER REMOVAL. 

Figure 6.- Measurement of radioactivity on daily filters from the 
air monitor (measurement from isotope analysis unit). 



562 















— 


^ 














— 


OQ 














— 
















- 


s t 
















m 










l« 














?• 














('•• 


— 


a 






< 


1 


• 


t 


— 


15 20 
UGUST 










s 


- 


o < 
1—1 










1^ 


- 


UN 










■ 


















« 






■ 


1 


4 « 


— 


















-* -3 












■ 




— » 










< 


) om 




1— 1 










• 




— 


UTS 










• 


















« 










• 




• 






lA 






• 


i 




00 




CM 






• •' 




■ 




— 


8 




■ 










— 


5 10 15 
JUNE 



CO 
Ixl 

—i 

< 

to 






o 
o 

o 

< 

QQ 



o 

•l-f 



o 
o 

> 



0^ 


a 




^ 


o 




CO 


1§ 




o 


u 
o 


• 




«M 


•a 






S3 


i/t 


i-H 


rn 


UJ 


a 


•rH 


«i 


a 


[Q 


Q- 


>. 


S 


13 


S 


U 


i 


1— 


a 


8* 



M 






0) 

a 

u 
CO 



u 

s, 



o 

03 

.iH 
-M 



•1-1 



NO 



iTk 



cri CM 

yH/SilNn 



565 



BODY FLUID AND BODY COMPOSITION MEASUREMENTS 

By A. A. Kelton, Ph.D. 
McDonnell Douglas Astronautics Company 

SUMMARY 

Measurements of plasma volume, blood volume, and total body water 
with radiopharmaceuticals, and also measurement of total body potassium by 
natural '^^K did not reveal any large changes in whole-body fluid compartments 
or lean body mass for the test or control subjects during the. 90-day 
test in the Space Station Simulator. Although the changes in body fluids and 
lean body mass were of marginal significance, the combined results are 
believed to reflect differences in the physical activity among the subjects. If 
valid, the results suggest that a rigorous physical conditioning program is 
necessary to maintain body composition in such a confined space. This study 
further indicated that improved methods for measuring body fluids and body 
composition must be developed and tested in a Space Station Simulator if 
potentially hazardous changes in body fluid compartments are to be adequately 
monitored for the zero-g environment of long-duration space flight. 

INTRODUCTION 

Measurements of whole -body fluid compartments and lean body mass have 
become high priority requirements because of evidence of major problems in 
adaptation to zero gravity. These problems are not only of scientific interest 
for Skylab and Space Station studies, but may endanger the health and safety 
of astronauts for long-duration space flight. Since alterations in fluid voluraes 
and lean body mass may also result from the inactivity associated with con- 
finement, any changes that occur in a simulated environment at earth gravity 
must be documented to establish a baseline for interpretation of changes at 
zero gravity. In addition, measurements of body fluids and lean body mass 
are required for a more accurate interpretation of medical measurements 
used to monitor the health of the crew and determine any biological effects of 
the environment in the Space Station Simulator. 

As a consequence, total body water, plasma volume, blood volume, and 
K content of the whole body were measured as a part of the medical monitor- 
ing program for the crew of the Space Station Simiulator during the 90- day test 
of a regenerative life support system. 




565 



EXPERIMENTAL PROCEDURES 

Radiopharmaceutical Procedures 

Using radiopharmaceuticals, total plasma and blood volumes, total body 
water, and lean body mass were determined for six normal, healthy, young 
(age 21 to 35) male volunteers. Two individuals served as normal controls 
and the other four were crewmen in the Space Station Simulator (SSS) for 
90 days. Baseline determinations for all six individuals were obtained 
6 days before the entrance of the four experimental subjects into the SSS. 
This allowed partial, esicretion of the radionuclide burden, especially 
tritium, biefo re the sim,ulator study. The three determinations were 
repeated oh the same six individuals immediately upon egress frona 
the 90 -day test. In addition, a total body water determination with tritium 
was performed on the 61 st day of the sim.ulator run by having the subjects 
drink tritiated water stored on board. 

The plasma and blood volume determinations were made by 
M. B. Cohen, M. D. , a consultant and medical specialist in radioisotope 
methodology. Using standard medical procedures, plasma volume was 
fneasu^red by intravenous injection of 10 [i.Ci of ^^^I-RISA for each determina- 
tion. * After allowing a 15-nriinute interval for equilibrium, a blood sample was 
taken by venapuncture. Plasma volume (PV) was determined by 

PV - (^P"^ /"^l of standard solution) (dilution factor) (ml injected) 

cpm/ml of postinjection sample 

Total blood volume (TBV) was determined from the hematocrit (Hct) as 
follows: 

rpTisy _ Plasma Volume 
^^^ ~ 1 - (Hctx 0.91) 

The counting error was always reduced to less than 1 percent. 

Total body water (TBW) was determined with tritiated water ( H2O). 
Total body waters were measured by and under the supervision of 
N. Telfer, M. D. , in laboratories in the medical school of the University of 
Southern California. Approximately 1 ml was mixed in a drinking cup of water 
and administered to the subject orally. A second l-mil sample was kept as a 
standard. Accurate determination of the dose and standard was made by 
weighing the syringes with the tritiated water before and after administration 
on a laboratory balance accurate to 0. 001 mg. Urine speciraens were collected 
from each subject at 3 and 5 hours. Water was separated from electrolytes, 
protein, etc., which interfere with counting, by freeze-vacuum distillation. 



566 



One ml of the distillate was added to the counting solution and the standard 
and samples counted in a liquid scintillation counter. 

/-I If rmaur it \ |i.Ci administered 

Calculation: TBW (L) = ^ „. ,^ . \ — 

^ |jlCi/Li m sample 

Because of the reclamation of drinking water fromi urine during the 90-day 
test, the routine determination of TBW was modified. For the baseline deter- 
minations, the subjects were given about 20 percent of the usual dose 
(150 [JiCi), or 30 |j,Ci of tritiated water. The onboard dose given on the 61st day 
of the test was also 30 jJiCi. The subjects were each given a 90 (aCI dose after 
egress when they were able to utilize biological excretion to reduce radiation 
exposure. The maximum counting error for the sample was 2 percent. 

Potassium-40 Measurement 

The natural content of potassium-40 was measured in the same six 
subjects 3 days before the 90 -day test and on the afternoon of egress. 

Measurenaents were performed in the total-body counter at the University of 
California at Los Angeles under the supervision of' N. S. Mac Donald,, Ph. D. The 
total-body counter was calibrated in terms of total potassium before the 
measurements. Natural potassiura-40 and total potassiumi exist in a fixed 
ratio in biological materials. 

RESULTS 



Plasma Volume and Blood Volume 

The results of plasma and blood volume measurements are shown in 
table 1. The precision of the mieasurement of plasma volume has a coefficient 
of variation of less than 1 to E percent. Significant differences (increases) in 
plasma volumes were observed in three of the four test subjects. Blood 
volume determinations were less accurate, but differences may have been 
measured in two of the test subjects and both control subjects. However, none 
of the changes can be regarded as significant since they lie within the range 
of normal human variation. Nevertheless, since the subjects acted as their 
own controls, such changes maybe considered indicative. 



567 



Total Body Water 

Table 2 shows the measurements of TBW of the subjects during the 
90-day test. Measurements were made before the test, on day 61, and 
immediately upon egress. Unfortunately, the standard for day was lost 
enroute to the laboratory so that the absolute values of these measurements 
are unknown. The day values were calculated from the relative determina- 
tions, the specific activity of the original solution, and the dilution factor. 
As a result, the changes noted in TBW for each subject are not meaningful. 
However, a comparison of the relative changes between subjects and controls 
might have soine indicative value since the precision of measurement should 
be about 1 percent. Thus, analysis of the data with the "t" test for unpaired 
variates shows that the average gain in TBW for the subjects was greater than 
the gain in TBW for the controls at the 90 percent level of confidence. Con- 
sequently, some increase in TBW for the crew may have occurred during the 
90-day test. 

Potassium-40 



Potassium -40 was measured in the UCLA total -body counter pre- and 
post -test in order to determine whole -body potassiumi. These results are 
shown in table 3. Total potassium is considered to be an index of lean body 
mass. The normal coefficient of variation for the precision of the measure- 
ment of potassium is 2 to 4 percent. It was the opinion of Dr. MacDonald 
that test subjects 1 and 2 and control subject 6 showed a significant loss of 
whole -body potassium. There was no significant difference between the 
average changes in the test subjects and those in the control subjects. 

Absorbed Dose from Radiopharmaceutical Determinations 

125 
The calculated radiation exposure from I-RISA was 6-mrad whole 

body radiation for each of the two determinations (ref. 1) as calculated by 

Dr. Cohen. 

Dosimetry calculations for the tritium deterrainations gave a total 
body dose of less than 10 mrads for the three determinations combined 
(,N. Telfer, M.D, ,, and G. Harwood, Private Comraunications). These calcu- 
lations accountea for recycling of 3h20 during the 90-day test. 

DISCUSSION 



Although the changes in body fluids and lean body mass were, at best, 
marginal, the trend of the corabined results may reflect the effects of 
differences in physical conditioning of the subjects. A prolonged exercise 
program will generally increase blood volume and plasma volume. Thus, the 
increase in plasma volume and blood volume in crewman 3 may be the result 
of his intensive and prolonged exercise program after entering the SSS. 

568 



Crewman 4 appeared to be the best physically conditioned of the crewmen 
before the test and his onboard exercise would not, therefore, be expected to 
affect his plasma volume and blood volume. Crewman 2 increased his exercise 
program in the mid-30 days of the 90-day test and subsequently maintained a 
higher ergometer workload. This may have increased his plasma and blood 
volumes. The control subjects had sedentary jobs during the test which may 
account for their apparent losses in plasma and blood volume. In general, the 
same tendencies were reflected by the measurements of potassium-40. Those 
subjects showing decreases in total-body potassium indicative of losses in lean 
body mass also exercised the least during the 90-day test; while thos6 subjects 
pursuing a prolonged and rigorous exercise program showed a tendency to 
maintain or gain lean body mass. If the foregoing observations are valid, the 
results suggest that a rigorous physical conditioning program is necessary to 
maintain body composition in a confined space. 

The results of the total-body water measurements were particularly 
disappointing. The spurious data obscured any meaningful interpretation. 
Nevertheless, some credibility should be given to the relative intercomparison 
of data and the measurements which followed egress from the Space Station 
Simulator. These results indicate that the test subjects had a greater amount 
of total body water that would be predicted from body weight. Further, the 
crew showed a greater increase in total body water than the control subjects. 
However, such results are not in general agreement with the measurements 
of plasma and blood volumes and total body potassium or the differences 
in physical conditioning of the crew. It would seem that any increase in 
total body water should be accounted for by some environmental factor that 
was common to the entire crew other than exercise. 

One obvious result of this study was that current raethods of measuring 
body composition and fluid compartments would be inconvenient, traumatic, 
and subject to uncertainty if the measurements had to be regularly performed 
in the actual environment of a Skylab or Space Station by inexperienced per- 
sonnel with onboard equipment and materials. Since the health and safety of 
astronauts may be endangered by changes in body fluid compartments in a 
zero-gravity environment, methods of measurement must be developed for use 
in spacecraft which are accurate, reliable and noninvasive. Recent innova- 
tions which measure trace amounts of deuterium oxide in saliva samples by 
infrared spectrophotometry or gas chromatography should be evaluated. Elec- 
trical measurements such as whole -body impedance and high sensitivity 
nuclear magnetic resonance are promising techniques for determination of 
total body water, extracellular fluid, and intracellular fluid. Prototype mea- 
suring systems should be evolved and medically evaluated during future, longer 
duration, naanned, one-g simulations. 

EEBEREHCE 
1. Hairper, P. V.; and Lipscomb, C: J. Wucl. Med.", 5:508, 196k-. 



569 



</> 


0^ 


h- 


O 


o 


1— 


Uj 


3 


QQ 




^ 


s 


to 






CO 


UU 




O 


z 


CO 


O 


s 


!< 


— 3 


1- 


-J 


co 


o 




> 


^ 


o 


sc 


o 


ou 


o 


CO 


_J 




CQ 


< 




g 


< 


1— 




CO 


< 


Ul 


s 


h- 


CO 


>- 


^ 


2 


1 


o 


r-l 




a 




CQ 




< 







uul 
































Ij 

IlU 




CM 




CO 


CM 


CM 






5^ 


Cf\ 


^"^ 


OO 


crj 




V) 


NO 


esj 


ir\ 


^J 


1— ( 


CM 




< 


+ 


+ 


+ 


1 


1 


1 




CO 
















< 














3 


^ 


^ 


r** 


^ 


OS 


UN 


»— • 


^ 


>- 


^ 


S 




^^^ 

^ 


s 


S 


s 


< 


'^a-* 


KT" 






^•' 


'^•' 


3 
















_j 
















o 
















> 
















o 


o 


C^ 


u\ 


1^ 


CM 




cr\ 


o 

s 

00 


>- 


^-•i 




ITS 


NO 

1—1 

so" 

• 


CM 
OO 






o 
















UJ 
















1— 


8 


s 


s 


§ 


8 


S 




o 

UJ 
Ol 

a. 


r*- 


en 


o 


CM 


o 


■«a- 




"^•^ 


"^"^ 




us 


'^'' 


'^•' 


















Ui 
















z 
















a 


















S 




8 


i-H 


^ 


S 




CO 


1 


+ 


+ 


' 


1 


1 




< 














^•^ 
















g 


^ 


f— 1 


S 




fO 


^ 


^ 


LU 


>- 


cr» 


CM 


u\ 


OO 


iTk 


^ 


< 


cvT 


CNf 


m" 


rK 


CM* 


cm" 


.mJ 
















o 






























< 


>- 


i 


^ 

r^ 


1— « 


^ 
^ 


OO 


i 


3 


o 


esf 


esT 


K 


crT 


cm" 


cm" 


ex. 


















I— 
















o 
















uu 
















CO 


1—4 


*^ 


c^ 


^ 


lA 


MD 




















CO 















o 



UJ 



CO 



o 



3: 

C3 



>- 
o 
o 

CO 

o 

^ • 



vo 

to 



S8 



5S 
SO 

O ^ 

CO Q^ 



570 






Z 

< 
m 



UJ 



CD 


C^ 


^ 


o 


i^H 


f— 


0^ 


3 


ca 


=) 


CO 


:s 


& 


CO 


UJ 
QQ 


o 


ZD 


H- 


CO 


< 


U- 

o 


1— 
CO 




UJ 


OC 


o 


UJ 

5 


£ 


^ 


CO 


>- 


< 


O 


u. 


O 


o 


QQ 






1— 


_J 


CO 


<r 


UJ 


t— 


1— 


o 
1— 


>- 

< 


1 


o 


CM 


s 


a 


o» 


QQ 




< 





UJ 

O 

z 
< 

X 

o 

I 



H- 
U 
Ul 

2 

CO 






(O 



—1 

o 


o 
w 


H 






UJ 


8 


Ul 




cc 


J 


u 


o 


z 


ra 




+ 


»- 



UJ 

z 



O) 



f 






-I 

in 

+ 






r^ 
«?>' 



O 

Ui 
UJ 



I 

< 

Z 
< 
UJ 



* 

UJ 

a 

z 
< 

X 

o 

i 



» 

o 

UJ 

ffiO 

r- UJ 

CC 



>- 
< 



u 

UJ 



00 p 00 

iri <e o> 
M ^ fO 




^ M «»• 
«m" I*.' 00 

"«* ^ «5 



(M m o CM rv o lo (o 00 

^f^i ii4 ^^^ 



-I 

o 

w 

■t- 



6 

I 



w 



o 
+ 



d 



q 



»- 


m 


^ 


(O 


o> 


a> 


r- 


<* 


ffi 


s 




in 




to 


^ 


5 


CM 


Q! 



(ooou) t^eqcq iq^^, 
"*55 555 m m to 



o f- o 



o »- o 



CM 



o «- o 



CO 



o «- o 



°5§ 



u> 



(O 



Eh 

o 



o 
w. 

o, 

S 

1X4 
P 

O 



^ O I— I 

— g 



571 



>- 

ca 

LU 

— ) Qi 

OQ uj 



CO 



o 
o 



— O 

CO DQ 

CO I 

2 fe 



3 



o 
o 

QQ 
i 

y 

o 



o ^ 



H- 


CD 




'SJ 


LU 


1 


OH 


O 


CO 


t— 


< 




LU 


— 1 


§: 


o 




o 



LU 

I 

CO 

< 







00 


CO 








CO 






CO 


CO 








CO 






o 


o 








O 


1— 




-J 


_-l 








—1 


z 




1— . . . 


t— 








h- 


LU 




z. 


"Z^ 










^ 




< 


< 








< 


^ 




<-> 


o 








o 


o 


















. . . .Liu . . . 


U- 








u. 


o 




CO 


z 
o 

CO 








z 
o 

CO 


>- 
< 


^ 


o 


cr\ 


CM 

• 


\r\ 


r^k 


CM 


o 


< 


o 


• 
ON 


^ 


• 

1— « 




• 

O 


1 

o 


r-i 
1 


1 


+ 


+ 


1 


r-H 
1 


o 




















CM 


r«- 


^ 


o>» 


f— 1 


r>- 




u-\ 


cri 


m 


CM 


vO 




« 


• 


• 


• 


• 


• 




CM 


CM 


CM 


CM 


CM 


CM 


ai 
















LU 

t 






























< 




















cy^ 


CM 


'S3" 


O 


NO 


C3 




Vi^ 


• 


• 


• 


• 


• 


• 




o* 


I— 1 


l»- 


CM 


i—l 


f— 4 


CM 






f— 1 


OO 
1—1 


o^ 

i-H 


NO 


NO 




5^ 


iT* 


^ 


£5!! 


h- 


r>— 


I-H 




r««- 


^O 


^ 


cr\ 


cri 


r- 


LU 
OH 




• 

CM 


• 
CM 


• 

CM 


• 

CM 


• 
CM 


• 

CM 
















o 
















LL. 
















LU 
















CO 




















O 


m 


CM 


'«3- 


O 


CM 






i-H 


• 

NO 

m 

1— 1 




1— 1 


I— 1 


• 
CM 

»— 1 




J— 
















O 
















LU 
















CQ 


■— 1 


CM 


tr\ 


■sr 


un 


NO 



CO 

o 



o 
o 

o 

z 
< 

CO 

— > 
QQ 

CO 



tu 

CO 

LU 

o 

z 



< 



o 

CO 

o 

z 



CO 



572 



SOME BIOCHEMICAL DETERMINATIONS ON SERUM FROM CREWMEN 

PARTICIPATING IN A 90-DAY SPACE STATION SIMULATOR TEST 

Edgar M. Neptune, Jr., Richard E. Danzlger, 
and Terry L. Sallee (Environmental Biosclences Department) 
and David E. Uddin (Clinical Medical Sciences Department) 

Naval Medical Research Institute 
National Naval Medical Center, Bethesda, Maryland 

SUMMARY 



Numerous alterations in the biochemical assays of serum were observed in 
the crewmen of the Space Station Simulator during and after the 90-day test. 
These alterations are evaluated In relation to the mean pre-test values with 
each man serving as his own control. Although the test was judged to be 
totally benign by the medical staff, the biochemical alterations are tenta- 
tively attributed to either the exercise program or the psychological or other 
stress factors. Final interpretation must await evaluation of these data with 
the data obtained by other research groups Involved in this study. 



INTRODUCTION 



A basic premise for the success of an operational orbiting laboratory is 
that man will be able to survive long periods of time under potentially 
stressful conditions. These comprise both physiological and psychological 
components, and can be divided most conveniently into the following: 1. Zero 
gravity, 2. prolonged exposure at pressures less than 1 atm, 3. trace compo- 
nent toxic effects, and 4. minimum contact with the "outside world" and 
resulting forced small group interaction. The recent study carried out for 
NASA at McDonnell Douglas Astronautics was basically an engineering exercise 
at 1 g designed to test the regenerative life support system and the feasi- 
bility of prolonged human habitation under these conditions. This test 
also allowed two types of biomedical analysis to be carried out. A small ali- 
quot of blood was drawn on board and subjected to routine clinical analysis 
under the direction of Dr. J. Wamsley (MDAC). The reported values were to 
serve as immediate clinical indicators to spot changes that might impair or 
abort the mission, or to determine if there were serious physiological changes 
that could prove injurious to the health of the subjects. A second set of 
samples was drawn for analysis of serum lipids, enzymes, and other minor bio- 
chemical constituents. These analyses were intended to provide information on 
the extent and nature of subtle biochemical changes which might be useful as 
indicators of stress. Changes In minor phospholipids have been reported to 
occur after acceleration stress, combat stress, and in schizophrenia (Polls 
e£al^. )(1). Data from these laboratories have indicated that severe psycho- 
logical stress may be reflected in serum lipids and it is well known that 

575 



there are hormonal and neurological factors controlling serum free fatty acid 
levels. Physical stresses and specific tissue damage are most conveniently 
assessed by examination of serum enzymes and isozymes. The nature and magni- 
tude of the changes observed in this test are correlatable with some existing 
literature; however, much of the information gathered is unique and will re- 
quire interpretation from a combination of physiological, psychological, and 
biochemical observations. 



METHODOLOGY 



Fasting blood samples were obtained between 0600 and 0700 by venipuncture 
using partially evacuated 15 ml containers. The blood was allowed to clot for 
30 + 10 min. The tubes were then centrifuged. Serum was withdrawn and 
placed in CHCl3-Me0H washed (lipid-free) screw-capped vials, packed in ice, 
and shipped via air freight to our laboratories. The analysis was begun 
within 24 hours of sampling. Commercial lyophilized serum was used as a con- 
trol for serum enzyme analysis. Pooled frozen serum, genetic type 2-1, was 
used for haptoglobin analysis. Chemical standards were controls for glucose, 
lactate, cholesterol, and free fatty acids. No satisfactory controls existed 
for the other determinations. Neutral and phospholipid distributions were 
determined by standard procedures developed in this laboratory (2,3), Lipo- 
proteins were determined by a modification of Noble's procedure with quanti- 
tation being accomplished by densitometry (4). 

Enzyme determinations: Total lactic dehydrogenasia (LDH) was determined 
by the method of Babson and Phillips (5). LDH isozymes were detected after 
electrophoresis in 0.97. agarose on microscope slides and quantitated by 
densitometry. The electrophoresis was carried out in 0.05 M barbital, pH 8.6, 
for 25 min at 150 volts. Alkaline and acid phosphatase were determined using 
Boehringer Mannheim kits. Creatine phosphokinase (CPK) was determined by a 
Calbiochem kit. Amylase was determined by a modified Cherry-Crandall starch 
hydrolysis method supplied as a kit from Harleco. 

Other serum measurements: Glucose was measured as true glucose by the 
glucose oxidase method (Worthington Glucostat'^) . Lactate was determined by a 
modification of the method outlined in Bergmeyer (6). Cholesterol was ana- 
lyzed by the Liebermann-Burchard reagent (Harleco) . Non-esterif led fatty 
acids were quantitated by a modification of Novak's method (7). 



RESULTS 



Table I indicates the analyses that were performed on the serum samples. 
Inspection of the test results showed that few components of serum were sig- 
nificantly altered by the 90-day exposure. Among the non-lipid constituents, 
glucose was quite stable with the only remarkable variation being a general 
small decrease in all subjects on mission day 53. The mean serum lactate 
values were found to range from 23-27 mg%. The serum enzymes showed some 

57^ 



regular fluctuations, but few clearcut changes relative to the test could be 
ascertained. Lactic dehydrogenase, acid and alkaline phosphatase showed no 
significant change throughout the test period. Creatine phosphoklnase (Fig- 
ure 1) was significantly elevated In crewman #2 on days 11, 39, and 60. 
Crewman #4 had hl^ CPK levels prior to the 90-day run, and these were further 
Increased during the run. These changes will be discussed In relation to 
exercise phenomena and adaptive changes. Serum amylase levels (Figure 2) were 
Increased over the pre-test mean in all subjects with crewmen #3 and #4 show- 
ing the most significant elevations. Of the serum lipid classes analyzed, 
the only noteworthy phospholipid change was in sphingomyelin (Figure 3) . A 
significant elevation of sphingomyelin was observed for crewmen #1 and #2 on 
day 18. Crewman #4 had an elevated value throughout the run while most of the 
values for crewman #3 ran below the pre-test mean. In the neutral lipids, 
cholesterol (Figure 4) showed a steady decrease during the run. The low 
values persisted throughout the post -test period. 



DISCUSSION 



In general the biochemical values that were determined over the course 
of this study indicate no marked alteration that could be Interpreted as 
hazardous to these men. 

One subject, crewman #2, had three elevations in creatine phosphoklnase 
after entry into the chamber, each elevation being lower than the previous 
rise. Such an Increase in CPK may accompany skeletal muscle Injury or severe 
exercise. A prolonged exercise routine can lead to progressively less signi- 
ficant enzyme changes resulting from an unchanged exercise regimen; this 
phenomenon, a type of adaptation, could possibly account for the pattern ob- 
served in this subject. 

Serum amylase was elevated In all subjects during the run. The origin of 
this enzyme (parotid or pancreatic) was not determined and no explanation for 
the rise can be offered at this time. 

In all of the subjects there was no detectable change In the minor phos- 
pholipids measured as the sum of phosphatidyl glycerol, cardlollpln and phos- 
phatidlc acid. If Polls (1) is correct that elevation of phosphatidyl gly- 
cerol is an indicator of "stress", no evidence of stress such as found in 
acceleration, conibat aviation, and schizophrenia was apparent in the chamber 
crew. The analytical techniques used by Polls, however, were different than 
those applied here, and direct comparisons are not possible. 

In all of the subjects the values for cholesterol fell during the test 
and remained low after the test. This could be due In part to diet and 
exercise but, without dietary analysis, this concept is only speculative. 
There have been reports of both a rise and a decline in cholesterol levels 
associated with exercise. 



575 



The sphingomyelin pattern is Interesting in all of the crew members. 
This phospholipid is increased in combat aviators (1). In an earlier study 
by this laboratory of isolation stress (unpublished data — Project RIM) one 
subject became very upset emotionally. At this time, his serum sphingomyelin 
was at these same high levels and remained higli for the next day even thougjh 
the isolation had been terminated. In our hyperbaric experiments on humans 
no rise in sphingomyelin has been observed. It will be interesting to see if 
these data show any correlation with the physiological and psychological ob- 
servations. 

The serum lipoproteins were considered to have shown no significant 
change. These analyses were performed because serum lipids are transported 
bound to proteins and, if there was a pronounced change in serum lipids, 
alterations in the lipoprotein pattern might be expected. 

Glucose and lactate showed no changes of any significance in this hypo- 
baric environment. 

When it was noted that one subject had an apparent ahaptoglobinemia 
prior to the test, the authorities on the test site were immediately notified. 
Examination of the subject, however, did not reveal any abnormalities. Sin&e 
haptoglobins are the normal mechanism for binding of free hemoglobin, a sudden 
decrease could indicate a hemolytic episode. 



REFERENCES 



1. Polls, B. D., Polls, E., DeCanl, J., Schwarz, H. P., and Dreisbach, L. 

Effect of Physical and Psychic Stress on Phosphatidyl Glycerol and 
Related Phospholipids. Biochem. Med., vol. 2, no. 4, 1969, pp. 286-312. 

2. Adams, G. M. , and Sallee, T. L. A Method for the One -Dimensional Thin- 

Layer Chromatographic Separation of Serum Phospholipids. J. Chromatog. , 
vol. 49, 1970, pp. 552-554. 

3. Sallee, T. L. , and Adams, G. M. An Improved One -Dimensional Thin-Layer 

Chromatographic Separation of Neutral Lipid Classes. J. Chromatog., vol. 
51, 1970, pp. 544-547. 

4. Noble, R. P. Electrophoretic Separation of Plasma Lipoproteins in Agarose 

Gel. J. Lipid Res., vol. 9, 1968, pp. 693-700. 

5. Babson, A. L. , and Phillips, G. E. A Rapid Colorlmetrlc Assay for Serum 

Lactic Dehydrogenase. Clin. Chim. Acta, vol. 12, 1965, 210-215. 

6. Hohorst, H.-J., in Methods of Enzymatic Analysis , ed. H. Bergmeyer, 

pp. 266-270. Academic Press (1965). 

7. Novak, M. Colorlmetrlc Ultramicro Method for Determination of FFA. 

J. Lipid Res., vol. 6, 1965, pp. 431-3. 



576 



TABLE I 



Serum Biochemical Analyses Performed During 
the 90-Day Space Simulator Test 



Neutral Lipids : Monoglyceride, free fatty acids, cholesterol, diglyceride, 
triglyceride, cholesterol esters. 

Phospholipids ; Lysophosphatidyl choline, sphingomyelin, phosphatidyl 

choline (inc. phosphatidyl serine and inositol) and minor 
phospholipids. 

Lipoprotein Distribution ; a. pre 6, 3 

Serum Enzymes : Acid phosphatase, alkaline phosphatase, amylase, creatine 
phosphokinase, lactic dehydrogenase 

Other Constituents ; Cholesterol (chemical) , free f iatty acids (chemical) , 
glucose, lactate, haptoglobin. 



5TT 




fr#NVWM3y3 



£ # NtfWMBHD 



E#NVnM3B0 



l#NVWMaaD 







CO 






a 


cu 






o 


:3 






•iH 


F— e 






CO 


a 






(0 


> 






•I-l 








a 


CO 
(U 






§ 






a 


■i-i 


1 

•iH 




+ 


m 


bfi 




f 


CQ 

3 






? 


U 


X! 






XS 


CO 




o5 


a 




• 

(U 

a 






TS 


■4-> 


? 


J^ 


o 


CO 


IV 




CQ 


-(-» 


to 


>. 




0) 


s 

TO 


X3 




(U 


in 


o 


> 


^ 




aJ 


•43 


-M 






o 

cu 

(0 
<li 
U 


s 

1 


f8 ° 


S 


c 




Q 




o 


in z 
CJ o 


■a 


>> 


s 


00 "^ 




-g 


1 


— 


cu 


CO 


T3 




Q 


cu 


XS 




s 


•4-> 




^ 
^ 


s 


1 

CO 


CO 


1 
7~ 




a 

XJ 


00 

— 


o 




cu 




GO 


■4-J 


-*-> 


^ 
^ 


r— ( 


01 
(U 

■4-» 

1 


OQ 
(U 

a 

'■a 


1 

8 


1— < 

a 


cu 
u 
a, 

cu 


1 


V 


B 


CU 


r^ 


CQ 


CU 


to 


1 

• 


cu 






r-f 




CU 




<0 


CO 


5 




U 
P. 


T3 



1X4 



578 



c 

O 
o 

0) 

o 
X 

to 
< 








o o o o 
o lo o in 
cj — — 



o o o o 
o in o lo 
CM — — 




o o o 
o in o 
04 — — 



^# m\NN\3hO 



£# NVWMaaO 2# NVIAIMiaO 



l# NVIAIM3aO 



00 



00 



1 



< 

Q 

z 

g 

to 
en 



<0 

§ 

XD 

C! 
O 

•iH 

03 
CQ 

•1-1 

a 

o 

CQ 



y 

CO 



o 

09 

a; 
> 

J— I 

a 

Q 






a 

-t-> 
CQ 

I 

> 

CQ 
(U 

■^ 

o 

•1-4 



CQ ^ 



a 



I— I 



^ 



S 



CQ 4.> 



I 



-t-» 



I— I ,Jh 

<y «*-! 

> Cl 

+3 O 

K ^ 

CQ > 

to -J3 

-M X, 

03 •*-> 

a s 
1 1 



CQ 

a> 

I 

CD 
U 



(U 



579 



b 



b 

CM 



c 

a. 

> 
o 

tr 



liJ 

>- 

O 

o 
I 

CL 




(M 



oo 



>* 
cu 



O <si 
CJ — 




f # NVIAIM3aO 



£ # (MVWM3aD 



Z # IMVIAlM3aO 



I # NvwAftaaD 



- 00 



o 
n 

oa 

a 
o 

•1-4 



0) 



be ^ 

•iH oJ 

03 '^ 

3 o 



(St 

a 

-M 

03 

O 

+J 

I 

u 

0) 
43 



Qi 
>. 

a 

o 

bfi 
S3 

•r-l 

•E 

03 

o 

CQ 
1— I 

> 
1—1 

a 

!h 
(U 
03 



CO 
•I-l 



0^ 
> 

■*-> 
o 

0) 

Pi 
03 
(U 
;^ 

03 

I 

CQ 

(U 



03 
O 

a 
-§ 

03 
(U 

I 

u 



o 
u 

S3 

o 

•1-1 

•>: 

TJ 

S3 
Oi 

-4-> 

03 

Q 
43 

■4-> 

03 

a 

T3 
<U 
(U 
U 
!>< 



580 







<M OO 

CJ — 



I ( I li 



i7^ NVIAiM3yO i.^ NVWM3dO 2^ NVWM3aO 



1^ NVIAIM3yO 





03 

1 

0) 


03 

0) 

a 

•iH 






r-i 


+J 




95 


a 


ea 




-»- 


0) 

4,J 


T3 




•♦- 


a> 






^ 


73 


§5 




00 


1 


-H 




00 


C! 


CQ 






O 


<U 




5 




^ 






CO 


cii 




S: 


a 


> 

01 




(0 


O 


1 




o 

ID 








to 


hD 


g 




in 


•iH 


•l-l 




1- 








m 
•^ ^ 


1 




5 


■TJ 


^ 




z 






§ 


8 25 
ISSIO 


m 
§ 


O 

ci 
3 


a 


- 2 


j^ 


T5 


-4-) 


= 


1— J 


1—1 


1 

o 


^ 


o 




u 




f-i 


■ 


a 


'J- 

1 






a> 




03 


0) 


J3 


— 


0) 

r— 1 


> 


-+3 


> 


O 


'43 


a 

o 


2 


•g 




1 


<M 


a 


^ 


0) 


o 


CQ 




lO 


a> 


a 


1 


03 


u 


o 


10 


1— 1 




•rH 


t 


(U 


•> 


-H 


1 


I— 1 


03 


e4 


to 
in 

1 




1 


o 


s 


TJ 




s 


GQ 


TJ 


^ 


^ 


0) 




I 


i 

• 


■4-> 
i 

o 


1 




-^ 


£24 


CQ 




o 


"S 


<D 




u 
PL 


i 





Pm 



581 



TQITILIZATION OF THE V-V SPIROMETER LOOP TECHUQUE 

FOR RESPIRATORY MONITORING 

:By 0. F. Trout, Jr., and T. 0. Wilsoa 
NASA Langley Research Center 

SUMMART 



The Y-T spirometer loop technique was successfully used in the 90-day 
manned test for respiratory monitoring. Only temporary small changes occurred 
in the respiratory systems of the test subjects during the test period, Becaijse 
the technique is easy to tise, requires Tery little time, and detects minor 
changes, it is recommended as a means of monitorijog the subjects in subsequent 
reduced-pressure-atmosphere closed-chamber tests and space flights. 

INTRODUCTION 

Pulmonary ftuaction measurements are useful in evaluating the condition of 
an individual's respiratory system and for detecting changes from disease, 
modified atmospheric conditions, and environm.ental contaminants. The volume — 
volumetric-flow-rate loop technique is a quick convenient method for obtaining 
simultaneoxisly several parameters of respiratory physiological data in a compact 
form. In this form the data are easy to compare on a time "basis and convenient 
to store. Although the technique is not in general clinical use, considerable 
research has gone into its development. (See refs. 1 to 9») 



SIMBOLS 

Y voltmie 

V volumetric flow rate 

DISCUSSION 



Figure 1 shows a typical V-V loop from a respiratory test. The curves 
indicate respiratory vol-ume as a function of volumetric flow rate for both 
inspiration and expiration. The inner loop represents normal tidal volume and 
volumetric flow rate, and the outer curve represents the maximum volxane and 
flow rate which the subject can achieve. The maximum volun^ which the subject 
can move in and out of his lU33gs is his vital capacity. The volximetric differ- 
ence between the inner normal tidal loop and the outer loop on expiration is his 
expiratory reserve, and the difference on inspiration is his inspiratory reserve. 

583 



Maximum volumetric flow rates are a measure of the elasticity and resiliency 
of a subject's lungs. 

Figure 2 presents a diagram of the apparatus used in the 90-day manned test. 
During a respiratory test, the subject "breathes into the spirometer through 
either a mouthpiece or a face mask. The spirometer is a l4-liter, positive- 
displacement-type device -with a lightweight "bellows. A pressure loading of less 
than 1 ram of water is required to move the spirometer "bellows; this thus causes 
a minimal pressure loading on the test subject. The spirometer produces simul- 
taneoiis electrical outputs for volume and flow rate. The dc signals from the 
transducer are amplified and fed into a storage oscilloscope. During a respira- 
tory test; the necessary information to complete the loop is stored on the screen 

of the oscilloscope. If the data loop is properly completed, the trace is photo- 

1 1 
graphed on a 3— -inch "by i|— -inch film with an oscilloscope camera. 

4 k 

Figure 3 shows the spirometer installed in the test chamber during the 
90-day manned test. During this test the V-'V' loop technique was applied to 
detect possi'ble changes in the su"bjects from contaminants, confinement, infec- 
tion, and the reduced- pressure mixed-gas atmosphere. 

Figure k shows oscilloscope traces of a person with no detecta'ble pulmonary 
system dysf-unction and of a person with marked dysfunction. This figure is used 
for illustration and is not of the su'bjects in the 90-day manned test. 

Figures 5 an<3- 6 show oscilloscope traces of test su"bjects 1 and 3 in the 
90-day manned test. Subject 1 had a smaller than normal vital capacity, whereas 
subject 3 had a greater than normal vital capacity. Q3iese loops show highly 
individualistic characteristics. Respiratory tests were performed on the sub- 
jects "before the 90-day manned test, once each week during the test, and at one 
and fovir days after the test. 

Ho major changes or infection were noted in the respiratory system of any 
of the test subjects. In the reduced-pressure atmosphere, the vital capacity 
of each of the test subjects decreased 5 to 10 percent while the maximim inspira- 
tory and esqpiratoiy volumetric flow rates increased from 5 "to 20 percent. Imme- 
diately after the 90-day manned test, "both tidal volume and volumetric flow rate 
returned to a value "between the pretest and test levels. Possibly Changes in 
the involuntary "breathing, pattern in the reduced-pressure atmosphere caused 
these minor changes; however, ftirther research is needed to confirm this effect. 

Small oscillations in the outer curve indicated very mild congestion for 
subject 3 "before, during, and after the 90-day manned test. This may "be a worthy 
su"bject for further investigation. 

CONCLUDING REMAEKS 

The volume — volumetric-flow-rate loop technique appears to have "been a 
useful method of pulmonary monitoring during the 90-day manned test. Respira- 
tory changes o"bseived during the test were relatively minor. The spirometry 

5^ 



eq.td.pin:eat operated satisfactorily during the test and required no repairs. For 
fubtire reduced-pressijre-atmosphere closed-chamber tests and space flights^ more 
ccanpact spirometiy equipniBnt is desirable and should "be developed. 

REFERENCES 

1. Burger, H. G.i Ihe Si©3,ificance of the Flow/Vblume Diagram in the Study of 

the Mechanics of Breathii^. Proc. Res. Counc. Royal Netherlands Tuberc. 
Assoc, Tol. 46, 1959, pp. 29-^5. 

2. Ilyatt, Rohert E.j Schilder, Donald P.; and Fiy, Donald L.: Relationship 

^tween, Ifeximum Expiratory Flov and Degree of Lung Inflation.. J. Appl. 
HQTsiol., vol. 13, 1958, pp. 351-336. 

3. Fry, Donald Le-wis: !Claeoretical Considerations of the Bronchial Pressure- 

Flow-Volume Relationships With Particular Reference to the Max±mum Expira- 
tory Flo-vr Volume Curve. Phys. Med. Biol., vol. 3> 1958, pp. 17^-19^. 

k. Fry, Donald L. ,: and Byatt, Robert E.: Rilmonary Mechanics . A Unified 

Analysis of the Relationship Between Pressure, Yoltme and (Jasflow in the 
Lungs of Normal and Diseased Human Subjects. Amer. J. Med., vol. 29, Oct. 
i960, pp. 672-689. 

5. Bartlett, Roscoe G., Jr.: Pulmonary Function Evaluation in Air and Space 

Flight. Afirosp. Med., vol. 32, no. 8, Aug. 1961, pp. GS^-Ssk. 

6. Dery, Donald W. ; Wiener, Leslie; and Hendler, Edwin: The Presentation of 

Flow-Vol-ume Loops. Preprint of Science Progress, I967 Annual Science 
Meeting, Aerosp, Med. Assoc, 1967/ P. 228. 

7. Carpentier, William Raymond: Measurement of Compliance and Resistance of the 

Lungs and QJhorax by the Use of Esj^dratory Flow-Tolume Curves . 
AMRL-^I}R-66-12, U.S. Air Force, Apr. 1966. (Available from DDC as 
AD 638 711-5.) 

8. Anon,: Biological Measuremeat of Ifen in Space. Tol. 1 - Biomedical and 

Human Performance Program. M6l-61t-l-I, Lockheed Missiles &. Space Co., 
Mar. 15, 1965. 

9. Stout, Bill D.J Wiener, Leslie; Deiy, Donald W.j and Cox, J. William: Clin- 

ical Application of the Flow-Volume Loop. Dis. Chest, vol. 55, no. 2, 
Feb. 1969^ pp. 101-lOij-. 



585 



VOLUME, 5 liters 



RATE, 5 I/sec 



CALIBRATION 
SIGNAL 



EXPIRATORY RESERVE 

VITAL CAPACITY 
EXPIRATORY VOLUME 




EXPIRATORY 
RATE 



INSPIRATORY 
RATE 



INSPIRATORY RESERVE 
NORMAL TIDAL VOLUME 



INSPIRATORY VOLUME 



Figure 1.- V-V loop method. 



SPIROMETER 




VOLUME 
TRANSDUCER 



DC AMPLIFIER 




POWER SUPPLY 



RATE 
TRANSDUCER 



DC AMPLIFIER 



STORAGE 
OSCILLOSCOPE 



Figure 2.- Diagram of apparatus for obtaining pulmonary loops. 



586 






Figure 3.~ Subject using spirometer during 90-day manned test. 



587 



o 


cr 


m 


LU 




!^ 


LU 


o 


CD 

< 


if) 




>~ 


J 


>. 


< 


< 


:^ 


UJ 




T 




:'**!^^?^S!^'^/'3*rr'5'i?!>'/'K^^--'«i!^S!f; 










U2 
3 



Co 
CD 
1^ 

1—1 

Clj 
CD 

:^ 

-M 
•iH 

s 

O 
U3 
1^ 
O 
O, 

M 

o 
m 

o 
o 



.-1 



I 

CD 
.'-I 



• ■ •..■■"i'F.^v,-.' ', 

' . # is*'?** 



588 





h- 




co 


o 


LlJ 


N 


h- 


\ 




OJ 


q: 


\ 


UJ 


0> 


h- 




ti. 




< 







a 



■»IK?iililP 






Slaia^!:.^3$Wf* 







Ear .-■ ^ -q^ WftBv '^^* 




-t tit.. 



!.<■■.■.■»■* 





H 






CD 




o 


UJ 




N 


H 




\ 






CM 


O 




\ 


z 




(J> 


tr 






^ 






Q 





IHyp^JSarK 









J,*!-*.; 









P 




_.„^ . -.- ... -. ...^m, ■ ■■■ '.^ji jtj^^i 

lll<W[liiMIHIHllllliili'iii'''l>" lir I il" i^fli 1' " ' "i iiM ■V*^'^'^; >-'' . ''< ' ^i'-jfSBE)-^ 







1 




h- 




(f> 




o 








yj 




CD 


o 

Ll. 
LlJ 
GO 








StBniiH^ 

IggBBM lUMfiBMM MMBMMSM I 



PI 

.«ia 











o 
o 

•I— a 

-o 

CO 

u 
o 

CQ 

a 
o 
o 

1—4 

o 

a 



in 

pi4 



589 





h- 




(f> 


o 


LlI 


N 


H- 


\ 




m 


q: 


X 


LU 


CB 


h- 




IL. 




< 



o P, 
f^ liJ 

\ ^ 
CD Q^ 

3 



O 
CO 



Biiiiiiiii 

CO 
IxJ 

o 



■iillKillKWnHiH'iii 



iSi 
















■"*""""" 'ft*''' 




! .;«■') 



W4»Vf^.#ri|t]e«MWV]' «<f«(,H»^- .M*Sta<HS«B*TStSfc,«k*as^^*5rtj,jw,,afe¥^^ 















CO 

o 

•r-s 

X5 

tn 
o 

o 
o 

F— ) 

c 
o 

a 



CO 



590 



BLOOD CARBOXYHEMOGLOBIN SATURATION OF PERSONNEL 

DURING NINETY-DAY TEST-""*^ 

By F. Lee Rodkey, Harold A. Colllson, 
and John D. O'Neal 

U. S. Naval Medical Research Institute 
National Naval Medical Center 
Bethesda, Maryland 20014 

SUMMARY 



Hemoglobin solutions prepared from blood clots have been used to meas- 
ure the COHb saturation of crew members during a ninety-day test of a Simu- 
lated Space Station (SSS) life support system. The Hopcalite toxin burner 
was effective in removal of CO from the system as rapidly as it was produced 
by the crew. During a period of 313 hours when the toxin burner was not 
operated, a total of 739 ml of CO accumulated in the gas and blood. An 
average rate of endogenous CO production over this period of 0.59 ml per 
man hour was calctilated. 



INTRODUCTION 



Control of the gaseous environment quality to suitably serve as the 
respiratory gas is critical when men are confined in a restricted space for 
long periods of time. Adequate removal of toxic materials is essential 
whether these compounds are produced by metabolic reactions of the crew or by 
chemical reactions related to operation of the equipment used. Adequate 
removal of carbon dioxide, produced in large quantity by the crew, and pro- 
vision for maintenance of appropriate oxygen levels are prerequisite to any 
such closed system. 

One such metabolic toxic material, carbon monoxide, is considered in 
this report. Although CO is released in relatively small amounts by off- 
gassing of many chamber materials (1,2), the contribution of the total CO 
production from this source in a satisfactory manned system is insignificant. 
Major sources of CO production, as from fire and overheating of organic 
materials, are to be scrupulously avoided. The endogenous metabolic produc- 
tion of CO by the crew members (3,4) is unavoidable and provision must be 

Supported in part by the Bureau of Medicine and Surgery, Navy Depart- 
ment, Research Task M4 306.0 2-40 30BAK9. 

The opinions or assertions contained herein are those of the authors 
and are not to be construed as official or reflecting the views of the Navy 
DepartB^nt or the naval service at large. 

591 



made to prevent its accumulation. Ideal CO control of the gas composition 
will result In a constant low level of carboxyhemoglobln saturation of the 
crew predictable from the known gaseous levels of O2 and CO. When CO is not 
removed from the gas phase. Its concentration will Increase from continued 
production by the men. The rate of CO accumulation. In both the gas phase and 
In the blood of the crew under these conditions, may be used to estimate 
the rate of endogenotis CO production. 



MATERIALS AND METHODS 



Blood clots remaining after serum renuival for other biochemical analyses 
were the materials used for COHb saturation measurement. The clots were air 
shipped In Ice, received In the laboratory In the original stoppered and la- 
belled tubes, and were refrigerated at 4°C without opening until the day of 
analysis. 

Hemoglobin solutions were prepared from the clots for analysis as follows. 
The tube containing the clot was opened and the clot transferred to a 20 ml 
plastic disposable syringe. The clot was expressed through the syringe orifice 
(no needle) back into the original tube. A volume of 2% Sterox SE in water 
was then added to the tube such that the volume of Sterox added was approxi- 
mately equal to the original volume of the clot. The tubes were stoppered and 
placed on a mechanical rotor at room temperature for 15 to 30 minutes to permit 
the Sterox to permeate the finely divided clot and hemolyze the red cells. 
The tubes containing the extracted clots were centrlfuged to obtain a clear 
supernatant solution. A fraction of this hemoglobin solution was transferred 
to a small vial or test tube for analysis of carbon monoxide content and total 
hemoglobin. 

Total heiK>globln was determined as cyaiunethemoglobin at 540 nm by use of 
a mM absorptivity of 11.0 (5,6). The reaction was allowed to proceed for at 
least 2 hours before absorbance measurements were made because of the slow 
conversion of COHb to cyanmethemoglobln (7). Usually a dilution of 1:301 was 
used: 15 ml of reagent plus 0.050 ml of hemoglobin solution. 

Carbon monoxide content was measured by gas chromatography (8). Condi- 
tions were used which prevented appreciable (X) formation during the reaction 
in the presence of oxygen (9). All results are expressed in terms of COHb % 
saturation calculated as 100 times the CO content of the sample divided by the 
total hemoglobin content of the sample expressed in terms of CO binding 
capacity. 



RESULTS 



Samples were obtained from crew members and back-up personnel over a per- 
iod of about 6 months before, during, and after the actual manned chamber 
test. These results in Table I show the values obtained, together with the 

592 



aean and standard deviation for each loan while he was breathing the uncon- 
trolled atmosphere of southern California. It Is apparent that four men were 
In the range given by McCredle and Jose (10) for normal nonsmokers (0.80 
4- 0.29) while the other three were more nearly like their series of smokers 
X4.13 + 1.99). Indeed one man had a mean COHb level of nearly 7% with one 
individual sample of over 9% saturation. 



Table I 

Blood COBb saturation of crew personnel for the 
ninety-day test while outside the SSS 



Date 


Donlon 


Dennis 


Wong 


Hall 


Hootman 


Shoemaker 


Dunn 


1970 


COHb 


COHb 


COHb 


COHb 


COHb 


COHb 


COHb 




% 


Z 


% 


Z 


Z 


Z 


Z 


3/24 


1.29 


2.74 


1.19 


1.35 


2.53 


1.45 


5.14 


4/7 


0.97 


5.02 


0.84 


0.95 


2.75 


0.98 


6.25 


4/14 


1.04 


4.98 


0.88 


1.05 


— »— 


1.19 


7.71 


4/21 


1.70 


4.06 


1.27 


1.42 


3.50 


1.02 


8.75 


4/28 


0.92 


3.92 


1.21 


1.18 


2.77 


1.22 


6.98 


5/5 


1.34 


3.18 


1.33 


1.04 


2.87 


1.07 


6.05 


5/26 


1.02 


2.88 


0.88 


1.08 


2.68 


0.93 




6/2 


1.09 


2.07 


1.31 


1.49 


4.65 


1.14 




6/9 


0.52 


0.95 


0.48 


0.85 


2.31 


0.87 




6/13 


Ninety-day test 


begins 










6/16 










0.41 


—— 




6/23 












0.60 




6/30 










2.06 






7/7 










2.18 






7/14 












0.99 




7/21 












0.61 




7/28 










2.50 






8/4 














9.05 


8/11 










3.14 






8/18 










2.97 






8/25 










3.09 


1.16 




9/1 










1.96 


1.13 




9/8 










1.67 


...^^ 


4.94 


9/11 


Ninety-day test 


ends 




4.07 


0.91 




9/15 


1.27 


1.39 


1.15 


1.28 


2.66 


_»». 


7.56 


9/29 


1.51 


4.37 


1.31 


1.25 


3.15 


2.11 


6.68 


10/6 


0.97 


2.41 


0.90 


0.95 


2.43 


0.80 


6.67 


Nuaber 


12 


12 


12 


12 


21 


17 


11 


Mean 


1.14 


3.16 


1.06 


1.16 


2.68 


1.07 


6.89 


S.D. 


+ 0.31 


+ 1.34 


-1- 0.26 


+ 0.20 


+ 0.86 


+ 0.34 


+ 1.32 



595 



Results obtained on crew nenbers during the actual nanned test are given 
In Table II. All these men were breathing the chamber gas and would be 
eiEpected to reach nearly Identical steady-state COHb levels (11). Minor vari- 
ation may be expected from differences in respiratory physiology among the 
men (12) . The mean COHb level observed for the four men on each day has 
been included together with the standard deviation. There is significantly less 
variation between the crew aenbers during the test than was seen for a given 
subject on different days outside the chamber. Furthermore, all the sub-- 
jects are in the range of normal nonsmokers. 

Table II 

Blood COHb saturation of crew members during 
ninety-day test inside the SSS 



Date 


Mission 


Donlon 


Dennis 


Wong 


Hall 


Mean 


Std. 


1970 


Day 


COHb 


COHb 


COHb 


COHb 


COHb 


Dev. 






Z 


Z 


% 


Z 


Z 




6/13 


1 


Men enter 


chamber 










6/16 


4 


1.11 


1.01 


0.95 


0.95 


1.00 


0.07 


6/23 


11 


1.58 


1.56 


1.58 


1.48 


1.55 


0.05 


6/30 


18 


1.76 


1.75 


1.80 


1.62 


1.73 


0.08 


7/7 


25 


1.77 


1.69 


1.53 


1.59 


1.64 


0.10 


7/14 


32 


1.81 


1.81 


1.76 


1.81 


1.80 


0.02 


7/21 


39 


1.87 


1.87 


1.86 


1.85 


1.86 


0.01 


7/28 


46 


1.72 


1.64 


1.65 


1.66 


1.67 


0.03 


8/4 


53 


1.66 


1.67 


1.70 


1.50 


1.63 


0.09 


8/11 


60 


1.54 


1.37 


1.40 


1.44 


1.44 


0.07 


8/18 


67 


1.32 


1.29 


1.20 


1.35 


1.29 


0.06 


8/19 


68 


Toxin burner turned off 








8/25 


74 


1.85 


1.94 


1.88 


1.93 


1.90 


0.04 


9/1 


81 


2.25 


2.42 


2.34 


2.32 


2.33 


0.07 


9/1 


81 


Toxin burner turned 


. on after 9/1 samples 




9/8 


88 


1.90 


2.01 


1.90 


1.93 


1.93 


0.05 


9/11 


91 


1.92 


1.75 


1.71 


1.81 


1.80 


0.09 


9/11 


91 


Men leave 


chaaber 











The mean COHb level Increased slowly from the test start until the saiaple 
on the 39th day, 7/21. After this a slow decrease was observed until 8/18, 
the 67th day. These changes reflect a change in the removal of CO from the 
gas by the toxin burner. This device converts CO to CO2 by catalytic oxida- 
tion on Hopcalite at about 370*C. Variation in the efficiency of CO removal 
as a result of alteration in gas flow to the burner or other factors probably 
explains the small changes observed for the samples from the start to 8/18. 

The toxin burner was shut down on 8/19 and remained off for a total of 
313 hours until after blood was drawn on 9/1. A significant increase of 
COHb from about 1.3Z to over 2.3Z was noted during this period. 

59^^ 



An approxlioate rate of endogenous CO production can be obtained from the in~ 
crease In the amount of CO In the gas phase and In the blood of the crew 
over this period. For this estimate, the actual volume of the SSS, 3,790 
ft^, was calculated to be 63.0 x 10^ liters (STFD). The Increase In CO con- 
tained In the gas was (63.0 x 10^ ml) x (20.5 - 9.4) x 10"° >» 699.3 ml. The 
Increase In blood CO during this period was calculated by estimating the 
total heBK}globin to be 10.1 g^/Kg body weight (13). The calculated values 
were Donlon « 7.66, Dennis » 9.59, Wong * 11.83, and Hall » 10.93, a total 
increase of CO In the blood of 40.0 ml. This gives a total endogenous pro- 
duction of 739.3 ml of CO In 1,256 man hours or 0.59 ml of CO per man hour. 
This result Is in quite acceptable agreement with the average value of normal 
endogenous CO production, 0.42 ml/man hour, reported by Cobum, et al. (4). 

The Haldai^ law for equilibrium distribution of oigrgen and CO in blood 
in man may be applied in vjvo in the following form: 

(COHb) (pBar""^7)fi02^40 

K » 218 " : • X --'—■ > ' 

0.97(100-COHb) (PBar~^^^^I^° 

in which COHb is the % saturation of hemoglobin with (X), (pg2|^-47)f j02-40 is 
the equilibrium oxygen tension, and (pg^^-47)f ^CO is the equilibrium carbon 
monoxide tension. This eqtiation is valid when the Inspired oxygen tension is 
approximately 150 mm Hg. In the steady state where (X) is excreted at the 
same rate as it is produced, the actual inspired CO tension must be less 
than the equilibrium CO tension by about 2 x 10~^ am Eg. Table III contains 
gas data from the SSS together with the expected CO eontaminatioa of the 
chamber gas calculated from the average COHb level of the crew and the anal- 
yzed oxygen content of the chamber gas. Identity between these two values 
was observed after recallbration of the IR instrument before the 7/7 8aBq»les, 
but usually the IR value reported from the chamber analysis exceeded the 
expected value by 3 to 7 parts per million. No adequate esqalanation for 
this discrepancy is apparent as in many cases the reported IR value actually 
exceeded the equilibrium value, a situation which certainly did not exist at 
any time in the 90'-day test as evidenced by the failure of the COHb of the 
crew and the CO content of the gas phase to increase as rapidly as would be 
required with the measured rate of endogenous GO production. 



CONCLUDING REMARKS 



These results d«Kmstrate that hemoglobin solutions prepared from blood 
clots may be nsed to accurately determine the fractional (X) saturation of 
blood. These data, together with the oi^gen content of the inspired air may 
be used to estimate the air CO contamination. In the steady state idiere 
endogenous CO production is exactly balanced by CO excretion, the equilibrium 
pCO of the blood exceeds the pCO of the inspired air by approximately 
2 X 10*"^ mm Hg. This value is determined by a number of physiological vari- 
ables including alveolar ventilation rate, lung diffusion capacity, rate of 
endogenous CO production, and al^molar oxygen tension. 



595 



Table III 

Blood COHb saturation and chamber gas relationships 
during ninety-day test Inside the SSS 



Date 


Mission 


Total 


Oxjrgen 


Average PEqCO 


fjCO 


fjCO 


1970 


Day 


Dry 
Pressure 


Fraction 


COHb calc. 
mm Hg 


calc. 


Obs .by 

IR 






mHg 




% x 103 


X 106 


X 106 


6/13 


1 


Men enter 


chamber 








6/16 


4 


507.5 


0.3153 


1.00 5.20 


6.8 


11 


6/23 


11 


516.0 


0.2984 


1.55 7.70 


11.9 


26 


6/30 


18 


509.0 


0.3045 


1.73 8.68 


14.1 


24** 


7/7 


25 


509.0 


0.3045 


1.64 8.22 


13.1 


13 


7/14 


32 


513.0 


0.3021 


1.80 9.03 


14.7 


8 


7/21 


39 


505.8 


0.3045 


1,86 9.30 


15.5 


12 


7/28 


28 


511.1 


0.2994 


1.67 8.24 


13.1 


12 


8/4 


53 


508.0 


0.3011 


1.63 7.98 


12.7 


18 


8/U 


60 


504.6 


0.3092 


1.44 7.35 


11.3 


20 


8/18 


67 


506.4 


0.3060 


1,29 6.41 


9.4 


16 


8/19 


68 


Toxin burner turned off 






8/25 


74 


507.1 


0.3060 


1.90 9.58 


16.0 


22 


9/1 


81 


511.5 


0.3126 


2.33 11.78 


20,5 


27 


9/1 


81 


Toxin burner turned on after 9/1 sanqples 




9/8 


88 


499.4 


0.3120 


1.93 9.71 


16.7 


15 


9/11 


91 


503.7 


0.3081 


1.80 8.96 


15,0 


18 


9/11 


91 


Men leave chamber 









**Error in calibration of IR instrument discovered. 



The toxin burner used in the SSS was effective in removing CO suffi- 
ciently rapidly to prevent accumulation of CO. The crew members were shown 
to form about 0.59 ml of CO per man hour or approximately 396 ml of CO by 
the 4 men per week. In the absence of (X) removal, toxin burner not opera- 
ting, the endogenous CO production from the crew can be estimated from the 
change in the total CO content of the gas phase and the blood of the men. 

The data presented indicate clearly that the instaneous range of (X)Hb 
in all members of the crew was extremely small. These comparisons were made 
without regard to exercise or sleep patterns and substantiate the Haldane 
espression wfaidi indicates that the major factor affecting the level of COHb 
is l:he ratio of p02 to pCO In the alveolar gas. 



596 



REFERENCES 

1. Hodgson, F. N. and Pustlnger, J. V. , Jr. Gas->of f studies of cabin mate- 

rials. Proc . Ann . Conf . Atmospheric Contamination Confined Spaces, 2nd, 
Dayton, Ohio, AMRL-TR-66-120 , 1966, p. 14. 

2. Rodkey, F. L. , Colllson, H. A., and Engel, R. R. Release of carbon monox- 

ide from acrylic and polycarbonate resins. J. Appl. Physiol. 27; 554, 1969. 

3. Sj 8s trend, T. Endogenous formation of carbon monoxide In man imder normal 

and pathological conditions. Scand. J. Clin. Invest. 1_: 201, 1949. 

4. Cobum, R. F. , Blakemore, W. S., and Forster, R. £. Endogenous carbon 

monoxide production In man. J. Clin. Invest. 42: 1172, 1963. 

5. Zljlstra, W. G. and van Kampen, E. J. Standardization of hemogloblno- 

metry I. The extinction coefficient of cyanmethemoglobln. Clin. Chlm. 
Acta 5} 719, 1960. 

6. Van Kampen, E. J. and Zljlstra, W. 6. Standardization of hemogloblno- 

metry II. The hemlglobln cyanide method. Clin. Chlm. Acta 6^: 538, .1961. 

7. Rodkey, F. L. Kinetic aspects of cyanmethemoglobln formation from car- 

boxyhemoglobln. Clin. Chem. 13: 2, 1967. 

8. Colllson, H. A., Rodkey, F. L., and O'Neal, J. D. Determination of carbon 

nK>noxlde In blood by gas chromatography. Clin. Chem. 14: 162, 1968. 

9. Rodkey, F. L. and Colllson, H. A. An artifact In the analysis of oxygen- 

ated blood for Its low carbon monoxide content. Clin. Chem. 1970 (In 
press). 

10. McCredle, R. M. and Jose, A. D. Analysis of blood carbon monoxide and 

oxygen by gas chromatography. J. Appl. Physiol. 22 : 863, 1967. 

11. Rodkey, F. L. , 0*Neal, J. D., and Colllson, H. A. Oxygen and carbon 

monoxide equilibria of human adult hemoglobin at atmospheric and 
elevated pressure. Blood 33: 57, 1969. 

12. Cobum, R. F. , Forster, R. E., and Kane, P. B. Considerations of the 

physiological variables that determine the blood carboxyhemoglobln con- 
centration In man. J. Clin. Invest. 44: 1899, 1965. 

13. Freyschuss, U. and Holmgren, A. On the variation of D^CO with Increasing 

oxygen uptake during exercise In healthy ordinarily untrained young men 
and women. Acta Physiol. Scand. 65: 193, 1965. 



597 



SUMMART AND COHCmSIONS 

J. K. Jackson 
McDonnell Douglas Astronautics Company 

and 

Albin 0. Pearson 
HASA Langley Research Center 

The 90-day manned test of a regenerative life support system has "been com- 
pleted with the accomplishment of the seven major objectives that were fonmu- 
3Lated during the initial planning of the progrsoE. The data obtained are ln5>or- 
tant to the scientific and engineering communities in \mdertaking the nation's 
fut\ire space effort. These data have been summarized in the preceding papers. 
Examination of these data is still underway, and useftil conclusions will con- 
tinue to be made for some time to come. However, the following conclusions and 
recommendations may be made frcan the evaluations that have been undertaken to 
date: 

Attaiimient of program objectives: 

(1) The 90-day test was completed without resupply of expendables or 
equipment; hence the biological and chemical isolation of the space 
station simulator (SSS) was maintained. 

(2) The regenerative life support systems operated effectively in pro- 
ducing potable water, removing atmospheric contaminants, and recovering 
oxygen from carbon dioxide. 

(3) Provisioning of spares, tools, and expendables permitted mission 
completion. 

(4) Data were obtained that defined system and subsystem mass and thermal 
balance and power requirements. 

(5) All maintenance and repair of the onboard equipment were conducted by 
the test crew. 

(6) Data on planning and procedures and corresponding crew performance 
were obtained and can be used to determine the capability of man in 
performing in-flight experiments during space missions. 

(7) Data were obtained on physiological and psychological effects of con- 
finement on the test crew, including group dynamics and the effective- 
ness of planned work and rest cycles. 

Evaluation of advanced subsystems: 

(1) Data were obtained on the perfoxmance of the vacuum distillation and 
vapor filtration unit, the solid amine CO2 concentrator, the water 

599 




electrolysis units, the two gas controls, and a mass spectrometer 
atmosphere sensor. 

(2) Further development of water electrolysis is necessary to meet flight 
operational reliahility requirements* 

(5) Incidents occurred during which several units were subjected to tran- 
sient output demands which escceeded their capacity. This result 
emphasized the rec[uirement for subsystem designers to provide for 
adequate margin to allow recovery from high loads, and for systems 
integrators to specify design parameters that minimize transient 
demands. 

Subsystem performance: 

(1) IThe relative importance of various unit performance characteristics 
was emphasized hy integrated system testing hut frequently was not 
pointed out "by subsystem design studies or test experience. 

(2) The results of the material selection program and performance of the 
trace contaminant removal equipment were such that the atmospheric 
contaminants were, in most cases, lower than those found in nomial 
amhient atmosphere. 

Food management: 

(1) Freeze dried diet could he acceptable for long missions. 

(2). Frozen food and selected snacks can he utilized in order to improve 
crew morale. 

(5) Microwave oven was inrportant for acceptability of food. 

{k) A method for reusing dishes and reprocessing food waste water is 
required, 

(5) Glycerol drink was accepted by crew and no adverse effects were noted. 

Waste management: 

(1) The commode was acceptable to the crew. 

(2) An improved urine collection, measurement, and sampling equipment are 
required far zero gravity use. 

(3) An improved means of handling waste and garbage is reqiiired. 

Equlpmenl: operation, maintenance, and repair: 

(1) Crew performance in operation, maintenance, and repair of equipment 
■vms effective and frequently ingenious. 

600 



(2) Automatic collection and display of data require improvement, partic- 
iilarly inside the space station simulator, to inrprore crew operational 
capability. 

HaMtaMUty: 

(1) The crew was ahle to adapt to and accept the living accommodations, 

(2) Crew recommended provision of abstract wall pattern (for example, wood 
paneling) on futirre missions to break visual m;onotoriy. 

(5) Crew would have appreciated shower bath facility. 

(k) Micro^ra,ve oven and food freezer were iniportant habitability features. 

Crew selection and training: 

(1) Crew selection criteria were established and provided effective 
qualitative guidance during the selection process because they were 

(a) Developed early in program 

(b) Provided effective guidance during selection process 

(c) Established an adequate local pool for subject selection 

(2) Crew training was adequate for support of mission objectives with the 
following exceptions: 

(a) More time, earlier in training program, wovild have improved 
crewmen's effectiveness during early test period 

(b). Availability of life support equipment earlier in training pro- 
gram was desirable 

Manned mission activity analysis: 

(1) Langley space station mission module computer program is capable of 
pravli3ing operationally acceptable activity schedules and facilitated 
incorporation of last minute changes. 

(2) Computerized activity scheduling is recommended for use in planning 
future manned tests in preference over manual scheduling. 

(3) Early start in task analysis and definition of constraints are 
Important, 

Behavioral studies: 

(1) Results indicate general low level of stress during test. 



601 



(2) Overt inter-^ and Intra- crev hostility seldom occurred. 

(5) Cr&vr showed decreasing morale through day 7OJ after that, day some 
inrprovement vas shown. 

Noninterference perfoimance assessment (UIPA): 

(1) HIPA appears to provide a method for evalviating crev psychosocial 
integrity on a real-time "basis hy observational techniques. 

Acoustic studies: 

(1) No general change in crewman sensitivity to noise. 

(2) Some loss in threshold hearing levels occurred in two crewmen. 

(3) Crew quarters noise level was acceptable (Acceptance level «* NCA 55) • 
(h) Eqialpment area noise leyel was marginal (Acceptance level « NCA 70) . 

Electroencephalograph (iSSG) - sleep studies: 

(1) Methodology was developed for obtaining and automatically scoilng of 
EEG sleep records. 

(2) Sleep records show little deviation from norm. 

(5) EEG/sleep analysis would provide valuable assistance in assessing crew 
mpod changes. 

JMedicaJL program: 

(1) There were no detectable adverse medical effects resulting from the 
90-day test. 

(2) Serum calcium and \xrine calcium were inversely related to CO2 partial 
pressure. 

Microbiology: 

(1) There was no clinical illness related to carriage or transmission of 
potentially pathogenic microorganisms. 

(2) The microbiological findings support the growing body of evidence that 
ground-based closed chamber tests do not markedly affect the micro- 
organisms or the sensitivity of the host to them. 

Radioisotope utilization: 

(1) Handling and storage of radioisotope heat sources in a closed environ- 
ment does not present a hazard to personnel. 

602 



(2) Better operational methads of measttring changes in "bcj^ fluid volumes 
are necessaiy for space flight use. 

Recaramended areas for improvement: 

[1) Zero G phase separators need to "be Ji5>roved. 

[2) I^ta collection and display should he automated. 

[3) Better design of cold-water dispenser is required for microhial control. 
[k) Closed-end crev tasks should he scheduled. 

5) Methods of dishwashing and reprocessing food waste water need to be 
developed. 

6) Qoboard laboratory should he esqpanded to reduce saatqple pass-out 
requirements. 

1 

7) The stan(fe.rds for potable water and atmosphere contaminants should be 
reassessed. 

8) The criteria, for wash water should be defined. 

9) Crew habitability in the areas of lighting, privacy, shower facilities, 
and color scheme shoxild be improved. 



NASA-Langley, 1971 



605 



National Aeronautics and Space Administraiion 
Washington, D.C. 20546 

official business 



FIRST CLASS MAEL 




postage and fees paid 

national aeronautics and 

space administration 



pnsTM A CTPD . If Undelivetable ( Section 158 
l^blMAbltK. po5,3, Manual) Do Not Return 



"The aeronautical and space activities of the United States shall be 
conducted so as to contribute . . . to the expansion of human knowl- 
edge of phenomena in the atinosphere and space, the Administration 
shall provide for the widest practicable and appropriate dissemination 
of information concerning its activities and the results thereof!' 

— National aeronautics and Space Act of 1958 



NASA SCIENTIFIC AND TECHNICAL PUBLICATIONS 



TECHNICAL REPORTS: Scientific and 
technical information considered important, 
complete, and a lasting contribution to existing 
knowledge. 

TECHNICAL NOTES: Information less broad 
in scope but nevertheless of importance as a 
contribution to existing knowledge. 

TECHNICAL MEMORANDUMS: 
Information receiving limited distribution 
because of preliminary data, security classifica- 
tion, or other reasons. 

CONTRACTOR REPORTS: Scientific and 
technical information generated under a NASA 
contract or grant and considered an important 
contribution to existing knowledge. 



TECHNICAL TRANSLATIONS: Information 
published in a foreign language considered 
to merit NASA distribution in English. 

SPECIAL PUBLICATIONS: Information 
derived from or of value to NASA activities. 
Publications include conference proceedings, 
monographs, data compilations, handbooks, 
sourcebooks, and special bibliographies. 

TECHNOLOGY UTILIZATION 
PUBLICATIONS: Information on technology 
used by NASA that may be of particular 
interest in commercial and other non-aerospace 
applications. Publications include Tech Briefs^ 
Technology Utilization Reports and 
Technology Surveys. 



Details on the availability of these publications may be obtained from: 
SCIEMTIFIC AND TECHNICAL INFORMATION OFFICE 

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 

Washington, D.C. £0546